First off I want to thank DSBJ for his DIY on the E92 coupe for M3 rocker panel install. His DIY gave me courage to tackle this on the E90 model. On to the DIY. With that said, do NOT
look at the E92 M3 rocker panel install as it is totally
different than the E90 install.
I will be listing the fasteners/rivot part numbers in this area soon.
starting out.....stock rockers
Tools needed: Flat blade screw driver, Torx 30 ratchet and needle nose plyers.
First step is situate the car in the best posistion to work on the rocker panels. My car is lowered on KW v1 coilovers and I decided to put it up on jack stands (in the front).
On the underside of the rocker panel you want to unsrcew the back Torx 30 plastic bolts that hold the rocker panel.
Once the black plastic torx 30 screws are all taken out you can manipulate the rocker panel a bit. You will want to go to the front of the rocker panel and pull lightly to pop out the rivots that hold the rocker panel to the body of the car.
Once you have the stock rocker panel off you can inspect it for existing rivots. If any rivots are still attached to the body of the car you can pry them off with a flat blade screw driver. see pics.
The white M3-specifc body rivot must be pushed into place as shown for it to work correctly.
White M3-specific body rivots installed
Next you will need to pull all but one of the green rubber grommets that are in the body of the car. These green grommets are for use with the 335-specific yellow clips that are on the stock rocker panels and are no longer used. YOU NEED TO LEAVE THE FIRST GREEN GROMMET IN PLACE AS IT IS USED WITH A 335-SPECIFIC YELLOW CLIP.
The rest get pulled out.
When installing the M3 rocker panel make sure to install the BOTTOM first. Slide the bottom UNDER the black felt under body cover, but make sure to get the rocker panel under the rivot that the plastic torx 30 screw goes into.
Once the bottom portion of the rocker panel is PLACED you can now line up the white M3-specific body rivots and push them into place. They will "snap" into place. Lightly push on each one to get it to "snap".
After the rivots are all in, now re-install the black plastic torx 30 rivots underneath the car. Again, make sure the black under body felt is OVER the rocker panel material. NOTE: For the area behind the front tire and in front of the rear tire will tuck in behind the rocker panel material.
Make sure that all areas are fitting flush.
Special thanks to LTBMW for making tweaks to the OEM M3 rocker panels.