I blew up my rear end last night in the Silvy and want to upgrade to a posi or locker unit. What 1/2 ton trucks came factory with the G80 lock or whatever it is called? Will it swap into a factory open rear? If not what are some recommendations for a good aftermarket setup?

Also did chevy make an aluminum driveshaft for a 4x4 RCSB truck? part number?
Thanks, TY