IRS equipped AU's can have either conventional or LSD diffs - LSD cars have a plate attached to the carrier saying HIGH PERFORMANCE USE APPROVED LUBRICANT ONLY. Having said that, the V8 should be
IRS anyway.
Grade . . . . . . . . . . . . . . . . . . . . . . . . . . Mobilube SHC ID
Ford Specification. . . . . . . . . . . . . . . . . . . ESZ M2C-190A
Mobil 3022 friction modifier.