Just checked my leftover in box. Look up the Timken one, it also gives the part number for the race and bearing. Rock Auto click on the Timken info page and you will get the info you need. Believe A2, 3, 6 etc... Was nomenclature for the bearing size. Timken box had SET2 and SET 6 labels, plus the longer part number.
I also have a set of rotors vintage from the day solid one piece, in excellent condition with the races installed if you need them. Did not realize they went out of stock on the 70-72 rotors. Calipers used to be readily available at local parts store too. These rotors were pulled from an E body that was converted to a race car.