All 8.25 rear ends had a 4.5" bolt circle. Starting in 73 the 8.25 replaced the 8.75 as the a-body heavy duty rear end. It could be had with cars with disk front brakes or v8 cars with 10" drums either case the bolt circle was 4.5". Only cars with the 9" drums had the sbp, if the 8.25 was ordered it required a brake upgrade which also came withe the big bolt circle.
