Originally Posted by 545felix

WORKS LIKE A CHAMP.

the wiring could not have been ANY easier. BMW was kind enough to leave an empty +12V on the fuse block just waiting for an M6 nut to hold the power lead on it. I ran the +12v behind the trim piece with the lighter plug in it, installed the amp on the left floor behind the tailight. there's a perfect ground there, thankfully rustproofing-free since the nut is in place when the body is dipped, so loosening the nut reveals a nice shiny clean ground. the amp barely fits under the trim panel, but it does close if I give the trim screw some gentle encouragement. a slightly smaller amp and you wouldn't even feel it.

the harness takes 20 seconds to install and is truly plug and play. plugged in my amp, tweaked the gain and crossovers, and presto, instant low-end response from the radio! everything turns on and off as it should, the amp power goes silent when the L7 amp does. brilliant. 5 days in and no increased battery discharge warnings, so it's turning itself off nicely.

I took pics, but I don't have my camera with me at work...i'll post some tonight.