OK then, if the balancer looks like Mark's picture, it's a cast crank 383. If it's low miles, then might be a good backup motor (maybe do a valve job). Otherwise, you could put your older forged 383 crank in there as long as you used a neutral balanced harmonic balancer (no weights)

70 Roadrunner convt. street car 440+6, NOS, 4-spd, SS springs '96 Mustang GT convt. street car '04 4.6 SOHC, NOS, auto, lowered "Officer, that button is for short on-ramps"