Steve,
I've got a 1982, 3.2ss (Mahle piston/cylinder set) with 964 cams. The distributor bushings went bad and I've been offered a 1978 distributor at a good price. I don't currently use the idle retard function and I *believe* the earlier cars had slightly more mechanical advance built in. Are there any issues with the 1978 distributor fitting in the block? I read a really old thread on the internet that early 78s had a different angle on the pinion gear, but that didn't really make sense to me. Anything is possible I guess. Emissions compliance isn't a concern.
Thanks!
KJ