[911SC Do it yerselfer]

Help, Tips?
I put a new clutch assembly (disc, pressure plate, throwout bearing, pilot bearing) on my 83 911SC motor. Both the tranny and motor are out of the car. Now that I try to slide the tranny and engine together they get stuck on something about an inch shy of coming together. I greased the Throw-out bearing, centered the disk, made sure the clutch fork slid into the T-O bearing, removed the starter in case that had something to do with it... still I can't get them together. I suspect the main shaft of the tranny may be getting stuck on the clutch disk but I can't say for sure. Any tips/advice?

Steve 83 911SC Cabriolet