['68OrangeSunshine]

I had an Auburn posi put in a 12 Bolt rear on my '67 K/10 Suburban in '96. Also had Moser axles custom cut for that build. [The GM factory was on strike at that time, so I couldn't get OEM axles.] Three years later, the 454 on the Sub had a fire and I ''downed'' the truck. In 2010, I blew out the factory Eaton Posi in the 12-Bolt rear on my '71 GMC Jimmy, so I cannibalized the differential off the suburban for the K/1500. Still on there now. Cuts tight turns.
We could not get the '71's wider rearend to fit on the '67. It's still on jacks until I can rebuild that rear.

Also, back in the '80s, I got an Eaton Posi on a 12-Bolt 3.73 rear off of a '69 GMC stepside in a junkyard. It was missing one axle so I got a new one from the Chevy dealer, and had a shop rebuild the carrier with new bearings and install it on my '68 C/10 stepside.

Both rearends are still going strong.