I am in the market for the 8.5 out of a grand national and i found one in the parts thread on this website. I am located in New jersey and the rear is in louisanna and i dont want to spend x amount on the rear and a buttload on shipping to just to have another non posi piece of garbage sitting in my yard. My question is, does anyone know how to identify that this rear is the real deal? Any part #'s or serial #'s on the rear that verify it is a grand national rear? I know that the bolt pattern on the 8.5 is different than the 7.5. Also thanks to the guys on this site i now know the difference between an open rear and a posi. But someone show me what i should be looking for before i drop the cash. Thanks alot.