Well, bought a Garmin GPS/dashcam with the rear view camera. I HATE wires around the console, so all power cables are hidden, only to the minimum length from the upper trim to the unit itself. Mounting the rear view camera was quite... interesting. There's a YouTube video that describes how to do the rear bumper removal. What it doesn't tell you is that the video is for the regular E63's, the M bumper cover attaches slightly different: there's no center plastic bolt, instead, there are 2 side plastic bolts. Then, the bumper itself is different, there's no way you can let it hang or put it on the ground as they show on the video: have several stands to hold it up to avoid ripping the wiring harness. No, it cannot be disconnected.

Then, the Garmin Camera requires considerable license mounting plate AND license plate trimming. Check if your local states allow you to trim the upper edge... actually barely visible, have to kneel down and look up... but then, there are cops and there are cops...but once you get the thing there it's nearly out of sight. And it will be obvious to thieves they will need to remove the bumper to get a functional unit out, unless their intention is to destroy it rather than take it.

Well, this brings us to the electrical wiring. The backup lights have THREE cables going to the bulb socket. Where do you connect? There's a connector near the split between the driving lights and backup lights. Peel back the cloth insulation, there you'll find 3 cables: brown (ground), yellow/white (backup lights) and yellow/red (driving lights). (mine is a 2007). I cut the cables and made the connections there, adding a small piece of wire to allow for the splicing loss (length). I replaced the bulbs with high power LED's for peace of mind.

The Garmin unit connects the camera to the windshield mounted unit via Bluetooth: you still need to get a good location of your transmitter to the receiver. Again, my OCD made me build a base that attaches the transmitter directly in line to the windshield mounted receiver without having any visible cables. And no rear view mirror problems either.

I realize there are many ways to do this, just wanted to get a feel of what other forum members have done. Easier ways ?? Clearly yes. Better ?? Show me. And no, I am NOT going to reply my own posts.