As Dave said just measure it as it comes apart.

Many....many years ago I built a truck motor to pull a large 3/4 ton camper and boat trailer. I used a 428 CJ block/crank and some heads off of a 332 motor. The 332 motors originally came with heads that had "machined" combustion chambers and the early large/tall intake and exhaust ports. I also used an aluminum Police intake with a single Holley. It was a great torque motor made out of parts I found kicking around the dealership backyard.