Just a quick note on bearing retainers. There was a 3sp in the 70's in trucks I believe that had the small bolt pattern(4.3"} for the early abody 4speeds that has the 5.125" index size. So I have a o/d bellhouseing with a 67 abody 4sp trany with a 3sp bearing retainer to match the trany and the bell. I also have a 4.8" bearing retainer that has the same bolt pattern as the o/d trany. Moral of the story is there is likely a bearing retainer made to fit whatever your combo you just have to do a little resurch.