Help identifying Disk brakes

I found these today in the parts stash... I've spent the last hour plus searching the net trying to find out what they are off of.

Caliper bracket says 90425

Caliper says KH90 795

Rotor says 934

The Rotors are 11.75"

I think these may be later B-body units but Im not sure.

If anyone has any Idea what they are or how to find out, Pease let me know.

Thanks,
C