Ring gear bolt shoulders to large to go through ring gear flange on sure grip.

I am in process of setting up a 3.23 gear set on a 1967 powrlok sure grip unit. Everything was going fine until I was putting the ring gear bolts in and found the new ring gear bolt shoulders are too large for holes in ring gear flange on the sure grip unit. I am using a new Motive Gear kit with new bolts. I looked in parts bin and found some old ring gear bolts out of an open carrier I had, they also do not fit. What gives? Were there different sizes ring gear bolts?