The big block version comes with a 5.125" bearing retainer bore. If you don't run an OD trans, you need an adapter ring. Since you're not going to weld on a SFI bell, what do you do? Sure, some of the later 833's can be fitted with a 5.125" bearing retainer, but the earlier ones with the smaller bolt pattern can't.
Seriously, I'm curious. There have to be tons of them out there, and I seriously doubt most folks are using an OD 833 with their big block Lakewood SFI bell.
