When I tighten the distributor down (stock 93 stang dist., new block), the distributor gear bottoms out in the block causing gear to bind. Does anyone know if they make shims for the housing to lift the distributor so this doesn't happen?
Unfortunately, it's not getting caught up on the top of the shaft. The oil pump shaft has plenty of clearance inside the distributor shaft. The problem is the distance between the distributor gear and the distributor collar...so when you slide it in, the gear hits bottom prior to the collar seating.
It sounds like you are putting a 351w dist. into a 302 block. Also, I think there were a couple of different lengths of 302 dist.
At this point it would probably be easiest to go to a good parts store (NAPA is the only one I can think of for this), and explain what the problem is. NAPA is usually more willing to pull parts off the shelf and compare to what you have. If Schucks can't find it on their computer it doesn't exist. (Sorry for the rant).