Possible to retrofit back up camera on older mercedes?
 

Sure, no trick at all. The easiest solution is to install a Gentex rearview mirror, which electronically switches from being a regular mirror to being an LCD monitor when you shift into reverse:


Color Back-Up Camera / Universal Monitor :: Sigma Automotive


You can mount it to the windshield, or there is someone here who figured out how to attach them to a Mercedes stalk.

There are any number of suitable rearview cameras, including a bunch of cheapo Chinese cameras on Ebay that can be painlessly swapped when they dim (they eventually always do). Electrical connection is simple: you need a switched 12V+, a ground, 12V+ from the backup switch and a thin coax connection to the camera.

I'm sure others have posted about this on the forum if you search enough.

I have a friend who put a Pioneer sound system with a backup camera (double din) in my '92 300D. He removed the ashtray to accommodate the Pioneer unit.

Buy radio that has rear camera out. Can be done

Here's the whole deal, cheap:


https://www.ebay.com/itm/Gentex-GENK322S-Auto-Dimming-Mirror-w-3-3-Monitor-Rear-Camera-Wedge-Mount/132637815453?epid=605433988&hash=item1ee1d4729d:g:mPUAAOSwQiFaVln1:sc:USPSPriority!10598!US!-1