WRONG , you have a early pre 1972 pulley versus a 1972 and later pulley that both could have came on a forge steel crankshaft in either year motor Trust us on this, your chasing absolute myths on this subject I have used the early pulleys on the later balancers by filing and elongating the odd ball hole to make it fit on the later forged steel crankshaft balancers
Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)
, you have a early pre 1972 pulley versus a 1972 and later pulley that both could have came on a forge steel crankshaft in either year motor 
