'96 M3 HK CD upgrade

[Jim Tappan <jtappan@xxxxxxxxxxxxxxxxxx>]

I recently purchased a '96 M3 Coupe with the upgraded Harmon Kardon
stereo, and am interested in adding the factory CD changer to the
system.  I  have been told and have also read on the digest about
choosing either the Alpine or Pioneer units.  My question is how do I
know which one will work?  

BTW: I know that you are supposed to press some combination on the head
unit to reveal the correct unit, but none of the combinations I have
seen yet works.  

Also, I am planning on installing a rear wing soon, but am struggling
with the decision between the factory M-Technic wing, M3 Lightweight
wing, or maybe a Schnitzer wing.  Anyone have any suggestions,
positives, negatives, etc...

TIA,

Jim
96 ///M3
CCA # Pending

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