Aha, Denny,
I know why neither of us knows what a 14 bolt is. And the later-post explanation is almost incomprehensible (complete sentences are lacking).
10.5” Corporate 14 Bolt Differential is a heavy duty differential that is used by Chevrolet and GMC trucks and vans since 1973. Of course it might have been a 14-bolt from 64 and later.
A good question from us would have been: "are you referring to a 9.5" or one of the 10.5" GM 14 bolt rear ends?"
