rear end problems

can anyone tell me what posi rear will fit in my 85 monte carlo, I mean out of what other cars. also is there any to tell a posi from a regular just by looking at them. :confused: any help would be great THANKS
Dennis

Any g-body rear will fit your car. For that matter, most GM rear's from that year will fit the car..
You need to be concerned with the gears and size.
3.73 7.5" is good for monte..
Try to get a rear from a grand natonal. :)