The previous owner of my car (95 E34) had the car wired for a cell phone. What remains of that installation is an antenna mount located in the top-center of my rear window, and a speaker phone box located on the pillar between the windshield and driver's side window. I'd like to disconnect them both.

The cable for the antenna mount connects to a module under the front seat. Can I disconnect the antenna under the seat and at the mount, and remove the wires? Any idea on how to remove the mount (there's a plastic piece on the inside and outside of the window). How about the speaker phone box? Can I simply cut it off and not do any damage to the car's electronics?

Also, there's a red light located on the back of the center console, that can only be seen from the back seat. Know what this is? It looks like there's a sensor located back there, too.

Thanks in advance.