Hey y'll, I just wanted to throw this up and out there for others thinking about doing this, to 'hand back' to the community I've been using for a few months now
I had wanted to do this for a while, as the previous owner somehow had decided to paint the diffuser insert in the M-Tech/M-Sport bumper body colored (instead of keeping it the more-aggressive stock matte black), and I thought 'why not make a little more aggressive/custom while doing the repaint'
For the $, the eBay diffuser/fins is a decent piece of kit, it isn't perfect (i.e. the spacing between the fins was off by say 1/8" to 1/4", but no one's going to notice!).
I definitely recommend buying their 'install kit' (a bunch of self-tapping screws, screw-clip sets, alcohol wipes and 3M tape) as used extra tape and self-tappers to hold to my bumper as want to makesure this doesn't get ripped-off.
It took a few hours to remove my bumper insert, clean/degrease, attach this diffuser part, then four (4) coats of Plastidip (prob the hardest part to get right in colder, wet 50F weather) to blend the bumper insert and this high-gloss black diffuser part together.
All in all, very happy, fun weekend DIY.
Parts procured:
+ One (1) "Fits 06-13 3 Series E90 E91 E92 E93 Rear Bumper Lip Diffuser 5 Fin Gloss Black" (
https://www.ebay.com/itm/Fits-06-13-...k/282075402977) $30
+ One (1) "Automotive 3M Installation Hardware Front & Rear Bumper Lip / Side Skirt Install" (
https://www.ebay.com/itm/For-Front-S.../282363340558?) $15
+ Two (2) Cans of Plasti-Dip Matte Black (
https://www.amazon.com/Performix-112...=fsclp_pl_dp_1) $6-8ea
+ Degreaser (to prep the parts before PlastiDip'ing)