C6AZ-6A312-A Two applications on 289 engines.
1. Manual transmissions and standard cooling (standard cooling is the 17 inch radiator).
2. All transmissions with extra cooling (extra cooling is the 20 inch radiator).
Dual belt alternator pulley, California emissions permissible. & Without air conditioning or power steering.
Ford casting number C6OE-6312-A. Double sheave 67 crank pulley. 6-5/8 inches in diameter.