The 8 1/4 thread

i just installed a newer ( with reluctor ring) posi carrier with 3.55 gears in place of the open 2.45 carrier in my ( 8.25 that came out of a 1974 dart) car. The carrier and pinion bearing sizes were different on each carrier but i just ordered new bearings to fit the 74 factory carrier and they fit right on the newer carrier and went right in with no issues. pinion was same inside and outside diameter on both pinions but bought new bearing anyway.

I have read where some people remove or grind down the teeth on the ring because it hits inside of the case. Mine did not hit so left it alone