you can source a mirror from only certain e30's
most e30 m3's
Old rear view mirror
The new mirror
Remove the lower dash panel
Remove a part of the door seal
Remove the hood hinge
Remove the speaker cover
Remove the speaker
Look for a black connector taped up in a harness
(excuse the wire taps they where there from a previous alarm i took it out but didn't take the time to remove each tap.)
Here it is plugged in
I plugged the harness in the speaker area, and fed the wire up top with a coat hanger,
Plug it in to the mirror and tested the bulbs
Install the spring into the frame on the roof.
It pops in sideways.
Plug the check panel back in.
Map light check
Check panel check
Possibly add led's inside these lights as they are not very bright