GM Dana 60-2? Is that even a thing?

[yossarian19]

An older gent locally sold me a Dana 60-2, representing it as from an early 60's GM product. It's six lug, semi float, ~61" wide across the drums, 12" dia. drums, and has a Dana power-lok in it. 3.54 gear ratio. Set up for leaves ~42" center to center. Has a "US PA 1968" stamp on the pumpkin but can't find a BOM tag on it.
For all the world, I can not come up with a likely vehicle this came out of. Parts catalogs don't list a 60-2 for any GM product, ever. The full size Jeeps went six lug in 1974. Ford was all 5x5.5" as far as I know. Mopar would be a maybe but again, six lug. So this leaves GM trucks with leaf springs, sounds like 1968... But the 60-2 cast into the pumpkin seemingly contradicts that.

Anyone able to shed some light on this for me?