Yes, your year would have the small bolt pattern and either 9" or 10" narrow 1 3/4"brakes. In '73, a 7 1/4 could be small bolt pattern with 9" brakes, or large bolt pattern with the 2 1/2" wide 10" brakes. The axle bearing changed on those big bolt pattern axles, and IIRC so did the backing plate from 4 holes to 5 holes (like the B and E-bodies have). I could be wrong on the backing plate holes however....I just can't remember for sure....but that seems to stick in my mind. Someone here is bound to have a '73-6 A-body with the big bolt pattern and a 7 1/4 to verify. I just don't have any factory parts manuals for those years now as I don't own one of those cars anymore.
