Radiator Opening

the factory radiator opening for that car is for a 22" core....the later A-bodys (73+) if equipped with a/c or the 340/360 had 26" core openings....it wouldn't be too hard to adapt one of those to work. That's one option, the second is get a good 3 or 4 row 22" aluminum radiator, and the third is to use the 26" rad in the 22" opening and swiss cheese the metal so airflow still passes through it. So long as you leave the raised ridge on the backside of the opening, integrity will not be compromised enough to really be an issue....