Immaculate low mileage 2004 Silver Grey CSL Inspired Build

[Kipjames3]

Were there any issues or concerns with the MEs front bumper? I'm getting mine installed soon and just wondering if you found anything wrong or that needed corrected with it.

[bavarian3]

Crazy impressive work as always! Looking forward to the next update.

Did you talk to the shop about paint brand? Glasurit yielded better(color match and clear coat quality) results than PPG in my recent experience and is what bmw factory uses afaik. If he's as good as you say then I'm sure you're covered either way!

BTW this seems like a good time for a CF roof just sayin =)

[Avedis]

After a year of researching body shops in my area, I found Dave at Premier Motorsport in Carson California by pure chance. Dave focuses on high end restoration of vintage and modern Ferraris. I dropped into his shop unannounced and he not only welcomed me, but gave me an hour of his time to discuss the project. He even gave me a tour of his shop, which was unreal. Behind the showroom stacked with supercars is a paint production area that’s even more impressive. It was ridiculously clean, sterile clean, with plastic curtains separating the different areas of the workspace. It seemed more like a science lab than a body shop. Multiple F40s, F50s, and a slew modern and vintage Ferraris, it was mind blowing. I wanted to take photos of the production area but it just didn’t seem appropriate. I did take some photos of his waiting area though.





Although Dave doesn’t normally work on BMWs, he agreed to take on the project. He cited my level of enthusiasm and how well kept the car was as the main reasons he wanted to work on it. After picking his brain for an hour, I could tell that he is probably one of the best painters in California and was absolutely the right man for the job. Dave is such a perfectionist that he wanted to do all of the fitting of the components to ensure it was to his standard. I advised him of this build project, build thread and my desire to work on the car myself. We came to an agreement where I would do all of the disassembly and test fitment so it could be documented, then I would bring it to him for sign off prior to paint. Dave would handle the paint, wet sand, and finish work, then hand the car back off to me for reassembly, final polish and ceramic coating.

We agreed on a price and start date a couple weeks out. This expedited my disassembly and preparation process.






You are probably wondering why I’m disassembling the entire passenger side of the car for a CSL front bumper, trunk lid and diffuser. When I first bought the car, the seller was transparent about the passenger side quarter possibly being painted by a previous owner. From what I could tell in photos and videos sent by the seller, the paint work was done incredibly well, and I was okay with it. Texture, color match, etc were all done with great attention to detail.

When I received the car, the paint was as advertised. Zero masking lines, orange peel was super accurate and the color match was about 90-95% accurate. Whoever did the paint did an outstanding job. That said, I found a tiny burn through in the clear coat where the rear arch meets the rear bumper and another one on the edge where the quarter panel meets the taillight.

Based on what I know about detailing and finish work, it appeared the body shop mowed down the entire panel with the massive rotary machine and wool pad. While rotaries make quick work of defects, especially in large areas, they can be incredibly risky on edges and adjoining panels. While 99% of people would never notice the burn through it bothered me and I wanted it fixed. It was also a good opportunity to go from 90-95% color match to near 100%.



After discussion with Dave, we decided to paint essentially the whole rear: trunk lid, rear bumper, rear diffuser, passenger’s side rear quarter including door jamb and a-pillar, and side skirt. This was the only way we could ensure perfect color match with the new components, while simultaneously repairing the rear quarter panel. In order to do this right, the front fender, front door, side glass and trim would need to be removed.

My little gremlins had some serious morning energy. I put them to work and made a 30 minute job of cleaning the wheel well liners into a 2-hour job. This of course included playing in the mud, and bath time.



I then moved on and pulled the windshield seals. The rear came off really easily and gave me false confidence for the front. The front was extremely difficult to get off. Parts of it came off without issue, but many parts of it required numerous tries and f-bombs to get it out. It came out in 10+ pieces, and I had to take multiple breaks in-between, but the job got done.





Afterward, I cleaned the channels really well and flushed them with hot water.




Up next was the rear quarter window and shadowline window trim. This required some interior panels to be removed, but overall the job was pretty easy.




Once the window was out, I could remove the rubber window seal, then the shadowline trim.




Next the lower rubber trim that sits on the quarter panel itself. The trim came off really easily but the adhesive was stubborn as hell. It required multiple rounds of adhesive remover soak then scrape with a plastic razor blade.





Here is the car almost fully stripped and ready for paint. I left a lot of little notes around the car for the painters. For example, how I wanted the CSL diffuser painted, how to remove the bumpers, and little areas that I felt needed extra attention.






In preparation for the return of the car, I purchased a ton of new clips, grommets, seals, screws, expanding rivets, etc. Sadly, this is what $400 of new genuine BMW hardware looks like, most of it you’ll never see.

[cornerbalanced]

I'd definitely consider it, but it would have to be picked up in the Los Angeles area. No time nor motivation to ship this thing.

Let's do it! I'm by Manhattan beach and work in Torrance - from memory we're pretty close

[Kipjames3]

When I purchased the Vorsteiner, it was a out a year before GT4 started making his. At the time, it was the best fitting and certainly the best 1x1 weave. It was also the only option that included "the ridge" that separates the carbon from painted section. Now, in 2025, the GT4 is a no brainer. I wasn't too bummed because I'm a weirdo and actually kind of enjoyed making it fit perfect, but most buyers would expect perfection at the $1400 price range.

He sent me photos of the diffuser installed and it looked great. I already heard good things about their bumpers so I thought why not grab both. He gave me a little discount also for purchasing them at the same time so couldn't pass that up. I have a Karbonius trunk and SG diffuser and I'm not super happy with the fitment (they were on the cars when I bought it), so I thought I'd just start from scratch with their diffuser and an OEM trunk. Patiently waiting for that to ship out from Schmiedmann but it's saying backordered until the end of May at the moment unfortunately.

[Avedis]

Great update. The replacement tips are genius! Care to share source?

I'm also about to start working on my CSL exterior parts and was wondering how to solve this since the oe tips may look funny. Most of the aftermarket muffler options don't seem to offer an oe-looking straight cut, chrome style. Curious what else you considered.

The tips are from a UK seller that mainly caters to the M3Cutters forum guys. They can be found HERE, not cheap, but were exactly the look I was going for, plus predrilled for E46 M3 pattern. If you are considering buying them, I would get them. When he sells out, he is out for literally months before a next batch is available. If you want straight cut single walled exhaust tips with slightly larger diameter, Burkhart Engineering sells sets in 70mm and 76mm.

Exhaust wise, I never really considered anything. I knew that I did not want to change out the muffler itself for anything louder, as I am really enjoying the CSL intake noise.

This makes me feel very good about my recent purchases of a Miles End diffuser and front bumper, and an OEM trunk. Everything looks great so far. I'm always looking forward to updates on this build.

When I purchased the Vorsteiner, it was about a year before GT4 started making his. At the time, it was the best fitting and certainly the best 1x1 weave. It was also the only option that included "the ridge" that separates the carbon from painted section. Now, in 2025, the GT4 is a no brainer. I wasn't too bummed because I'm a weirdo and actually kind of enjoyed making it fit perfect, but most buyers would expect perfection at the $1400 price range.

If you need to clear up space and end up selling your front bumper, I’ll take it! Mine has license plate holes.

Car is going to look fantastic once everything is installed.

I'd definitely consider it, but it would have to be picked up in the Los Angeles area. No time nor motivation to ship this thing.

[cornerbalanced]

If you need to clear up space and end up selling your front bumper, I’ll take it! Mine has license plate holes.

Car is going to look fantastic once everything is installed.

[fattycharged]

Bummer on the Vorsteiner, I saw some photos of a local one to me and it definitely had the same issues


Sent from my iPhone using Tapatalk

[Kipjames3]

This makes me feel very good about my recent purchases of a Miles End diffuser and front bumper, and an OEM trunk. Everything looks great so far. I'm always looking forward to updates on this build.

[bavarian3]

Great update. The replacement tips are genius! Care to share source?

I'm also about to start working on my CSL exterior parts and was wondering how to solve this since the oe tips may look funny. Most of the aftermarket muffler options don't seem to offer an oe-looking straight cut, chrome style. Curious what else you considered.

[0-60motorsports]

Awesome update. Always look forward to your detailed posts. I need to get those seatbelts done

[Avedis]

I then repaired the portion of the bumper that supports the bottom middle section of the rear diffuser. It looks like the factory pieces were just plastic welded onto the kevlar bumper bar from the factory. I mixed up some epoxy and resecured the mounts to the kevlar bumper bar. This should be significantly stronger than how the factory did it.




I got into a really nice work groove and was making progress fast. My plan for the day was just to do the exhaust tips and remove the rear bumper, but I did far more than that. I ended up removing the factory trunk and test fitting the genuine CSL trunk lid I had previously purchased from a forum member. You’ll see that it’s already painted, but the paint is in really poor condition and the whole thing will be getting restored. I threw the trunk lid on without making any adjustments from the factory trunk bolt locations. This is exactly why you go genuine on the trunk. It fit 90% perfect with zero adjustment.




I spent the next two hours (literally) learning how the adjustments on the hinges and bolts affected the fitment. I must have opened and closed the trunk 100 times, each time making micro adjustments. I got it really close but there are still some areas I will finalize after paint. I couldn’t resist throwing on the rear bumper and diffuser to see how it all looked.



Things were coming together really nicely and I just had to put everything back on for a quick mockup.



Next I jacked up the front of the car and removed the factory front bumper.


I pushed on the Mile End Composites CSL front bumper. Fitment was near perfect with zero adjustments. I simply pushed it on and snapped some photos of the alignment. One of the things I was pleasantly surprised by was that the factory non-CSL windshield washer fluid reservoir fit within the new CSL bumper. This was a really nice and thoughtful touch by Mile End.

I have some Trinity Graphics front and rear bumper mounts enroute. I will continue to tweak, adjust and document the process. Until then, we’ll leave it here.

[Avedis]

I’ve been collecting CSL exterior components for the last year or so, but I’ve been putting off paintwork for a couple of reasons. First, I wanted to focus all my attention and money on the interior first. Second, and more importantly, it’s insanely difficult to find a body shop in all of the Southern California area that I trust with this car.


Although I have yet to commit to a particular shop, I recently commited to starting this project. This prompted a whole chain of events: measure, disassemble, test fit, modify, order parts, and eventually, drop off for paint. This process will be documented over many posts moving forward. For the purposes of this thread, this will be considered Phase 2: Exterior Body & Paint.


First, I took measurements of all the panel gaps for the trunk, diffuser, front bumper, rear bumper, etc. This way I had a good reference moving forward on what the gaps were. The goal was to either equal or improve the existing gaps for the new components.





I then took all the CSL components down from storage. Penny (my golden retriever) knew something was up. She doesn’t normally come out to the garage but she wanted to check out what was going on. She was not impressed.




I started with what I thought would be the easiest of the new components, the diffuser. The factory diffuser (and 5 pounds of rocks/dirt) came off easily. The Vorsteiner diffuser got its first test fit. The fitment was 80% there with no modifications at all. The panel gaps were actually even better than the factory piece in most places.




That said, the top of the diffuser refused to sit flush with the bumper. If you look closely you can see it’s sitting about 1mm-2mm proud of the bumper.



There were two minor issues. One was that Vorsteiner made the center alignment tab too wide. It was just wide enough that it wouldn’t push fully into the hole in the factory bumper. This fix was really simple, open up the alignment hole in the bumper, and take a tiny bit of material off the diffuser.




The second issue was that the lip on the top/backside of the diffuser that hooks into the bumper varied in width. It was anywhere between 0.25mm and 2mm too wide compared to the factory piece. This fix was more involved. It required me to take measurements off of the factory piece, score the Vorsteiner diffuser with a micrometer, then use an orbital sander to shave down the lip, matching the dimensions of the factory diffuser.



First the top section.



Afterward it sat perfectly flush and the gap was far better than factory.



Then I moved onto the sides utilizing the same method. Take a little off then test fit. Repeat as necessary.




After those tweaks, fitment was perfect. Here you can see how I checked the alignment of the two pieces. Long story short, if you’re looking for CSL diffuser with zero fitment required, send Gt4 a message.



Next up was removal of the rear bumper.



While the bumper was off, I installed some “Eurostyle” exhaust tips. They are slightly larger diameter and have a more substantial dual wall design that I thought would pair really nicely with the new diffuser. First the factory rivets were drilled out. Then the tips were easily removed.



Here is a side by side comparison/mockup and a full mock up afterwards.





I couldn’t resist cleaning the area before installing the exhaust tips. After a deep cleaning session I measured the tips for perfect alignment, then secured with metal rivets.

[Abrajam]

wow, that things is NUTS

Now that the interior is done, I wanted to share some completed photos and summarize everything in one post. The interior portion of this build has been spread over ten different pages, and I thought it would be useful to have one post that contained everything I’ve been working on for the last two years.

First, the photos
















From the front of the interior to the rear, here’s everything that was done:

• Dinan brushed aluminum pedals.
• Custom / refurbished steering wheel, 1cm thicker diameter, smooth Nappa like leather, ///M colored tri-stitch. Blank upper trim (button delete), lower trim refinished in matte black.
• Steering wheel and dashboard airbags replaced under recall.
• Navigation delete, radio delete panel, new instrument switch panel, HVAC controls moved up, new lower sunglass holder.
• Z4 rear view mirror, manual adjustment with grey clown-nose alarm.
• New sunroof motor cover without home link and sunroof switch.
• New inner door handles without HK logo
• CSL front door panels in matte 1x1 carbon fiber, ceramic coated for a satin finish. CSL door handles in custom brushed aluminum finish. Sound deadening on back of panels. Door panel speakers deleted. Airbags deleted.
• CSL center console in matte 1x1 carbon fiber, ceramic coated for a satin finish. Mirror adjustment switch moved to center console. New hazard switch and mirror switch trim. CSL leather e-brake boot.
• Seat belt assemblies sent off and replaced with ///M colored tri-stitch belts. Factory seat belt tags were re-sewn on.
• Recaro Sportster CS front seats, custom Nappa like leather by AMX performance, ///M logo embossed in headrests, ///M logo tag sewn into side bolster. Seats were installed onto factory seat power sliders with custom seat brackets. Momentary switch was wired for forward and backward movement. New nuts, bolts and bolt covers for seat brackets.
• CSL rear door panels in matte 1x1 carbon fiber, ceramic coated for a satin finish. Sound deadening on back of panels. Door panel speakers deleted. Airbags deleted.
• Rear headrest deleted, headrest holes plugged with BMW blind plug. Rear center seatbelt delete.
• Rear parcel shelf replaced with European version (no LATCH holes), smaller speaker grills without HK logo. Rear deck speakers and subwoofer deleted. New through loading cross member trim. New rear seat belt outlets.
• New c-pillars and interior light bulbs.
• Amplifier, navigation and all other audio components deleted from trunk.
• Massive amount of new clips, screws and fasteners throughout the interior.

Phase 1 of this build complete.

[M3LSB.Gab]

that is one of a build and thread ! can't wait to see the DIY CF roof install and look with CSL front bumper !