Regarding stereos... any stereo of "standard" DIN size should fit.  DIN
just means that it is your basic sized stereo for a single opening.
Some may be a bit tighter than others and you may need to remove the
(speaker?) bracket that is in the middle of the dash behind the stereo
to make it fit, but if I can get my Eclipse deck in with it's 7 wire
pigtails and external digital converter you should be able to fit any
regular stereo in there.

-Nate
'84 Westy