Pic is a mopar 8-3/4" posi on Marketplace, says from a 66 Super Bee. But it sure looks like an Olds-Pontiac 9.3" posi differential though. I've noticed that when searching for 1963 Pontiac fullsize differential parts on Rockauto, it references many Mopar parts as well...initially I figured it was just part numbering data errors. So are they the same posi diff for both?
https://www.rockauto.com/en/catalog/...ion+yoke,13842