I would think you've got to find some head unit that accepts the plug from the 3CD stacker. (You probably already thought of that, but you didn't say so...

) I don't remember what the 3CD player plug looks like. FWIW, the 3CD player is a dumbed down alpine design. Maybe an old alpine head unit?
Cruise some junk yards for 626's... or I've got the old OEM cassette / radio if you want. It's been in a closet for the past eight years.
BTW, the 3CD player is just gonna crap out on you too.
