Tranny won't mount

Put a Centerforce dual friction in my 1970 Duster, 340 with the 833. When I try to slide the transmission on, it stops about 1/4 inch from the bellhousing. Worked on this for about 6 hours today. :banghead: Got some 3 1/2" bolts to put in the transmission bolt holes to help with alignment, didn't help. Splines are engaged, it slides back and forth on the alignment bolts easy but seems to hit something hard to prevent it going that last 1/4 inch. Did not replace the pilot bushing, but it looks like new and is not dinged up at all. Had a friend stop over and look at it and he thought everything looked correct and it should just slide right on also. What am I missing here?