Unless you are doing an OEM resto,you can switch the spindles to the 73/74 E/B body spindles. The calipers and hardware bolts up the same,but the one peice 73 and up rotor is available,and costs about $42.00 brand new compared to $250.00 plus for the two peice 70-72 rotors,if you can even find them. I have bought several pairs of those spindles in the $50.00-$100.00 range per pair.