I just bought that setup at a swap meet, then changed my mind about using it because I stumbled on a 73 and up big bolt pattern A body setup. The only spacer I saw was the one behind the rear seal for the back bearing. The SSBC brakes are a bolt on kit for A body Mopars like your 72 Dart. They bolt right on to factory 10" drum brake spindles. The calipers are the same thing as what would have came on your Dart, had it come with factory disc brakes. Mopar small bolt pattern rotors are 2 piece, but the Mustang rotors are one piece and have the slots in the side of the hub. You could move the wheel studs out to the 4.5 bolt pattern holes if you wanted. Look on your calipers and see if they have SSBC cast into the caliper body like the one in the pic below. If they don't, they are probably factory Mopar calipers. If your upper control arms have the small upper ball joint, it's more than likely an SSBC conversion. If you do decide to grab the Volare/Aspen disc setup, you will need some 73 and up, upper control arms that use the big ball joint because the F body spindle needs that ball joint instead of the small one. FABO member
@blewbyu lives in FL, and had some factory BBP disc setup cores for sale a while back, so maybe contact him to see if has any left.
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