The camera installation in my 1995 E300 (W124) is complete. It looks very much like Mach4's since it is the same camera installed in the same place. To connect power to the camera without cords dangling, I bought a small usb to mini-b retractable cord . . .
. . . and took it apart. The nice thing about this kind of cable is that it is essentially a tiny (flat) ribbon cable and so is easy to slip between the roof of the car and the header panel at the top of the windshield.
I built a power converter from a three-terminal 5 Volt regulator and put that in the overhead where the front dome light lives. The sunroof switch gets power whenever the ignition switch is in position 1 and so does the camera.
I notice that the camera's display stays on for a minimum of 3 minutes, then blanks. Not sure if this will be distracting at night; the camera is mostly out of sight in front of the rear view mirror. I suppose I could always put black paper over the display. I did put a piece of black electrical tape over the IR light, the only non-black part of the camera.
Jeremy
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"Buster" in the '95
Our all-Diesel family
1996 E300D (W210) . .343,000 miles
Wife's car
2005 E320 CDI . . 148,000 miles
My car
Santa Rosa population 177,300 (2026 projected)
Total. . . . . . . . . . . . 668,300
"Oh lord won't you buy me a Mercedes Benz."
-- Janis Joplin, October 1, 1970