Well after searching all over the web, I finally did the 1 hour topix subscription and pull together enough evidence to get into it.
1) The subwoofer is in the drivers fenderwell (huh?). You have to pull the wheel, and both liners. Not going to happen. Factory amp, nope too much. My goal - what’s the easiest, cleanest install with minimal impact and reversabable.
2) According to the wire harness, speaker wires (positive / negitive) are twisted together. Lot easier to find.
3) Wire harness mentioned above runs through the spare tire department. So no need to remove panels or mess with fender liners. In fact, I didn’t pull one single panel.
Super easy install. I used the bolt stubs within the battery compartment to fasten my amp down. It was a near perfect fit. No screws, holes, etc. Just a few metric nuts and washers.
Battery (+) straight to positive manifold (see pics) with fuse
Battery (-) to body using existing bolt stub (metric)
Remote (switched +) used a mini fuse tap, plugged into second (10 amp) fuse labeled stereo amp. The aftermarket amp only needs .5 amps to switch on
Signal - see pics for wire color. Used taps too, so that I can remove with minimal evidence. Only picked on channel, it’s subs.
Installed Lc2i to clean up the signal. Curious if needed, my Mercedes needed it really bad.
What’s great, I can control through the subwoofer settings on touch screen (like a remote knob).
See pics of install (before wire loop and finally clean up)
I know this isn’t everyone’s cups of tea... Cheers!