Just bought a 8 3/4 have a few questions?

I believe the point GJ was trying to make is that it is not a posi "type" diff. Posi, Sure-grip, and more recently "no-spin" are just the OEM nicknames given to a friction-joined type diff. The Dana or manufacturer name for their 60s-70s era clutch type posi's were Dana Powerlocks, for example. The later cone type models from Auburn were different types of the same technology, I just forget what Chrysler called them.

Semantics, man. No need to get picky about it.