Tbh I think my only possible point of contact is actually the center of the quench pad on the head; I’d rather grind that down a bit. I’ve said it here a bunch now but the 273, same stroke smaller bore; same rods and crank; and the same heads that I’m using essentially (they had 920 castings which are closed chambered with smaller calves than the 302) had optional dined pistons almost the same in shape and tan fine from factory. So I honestly think they should fit and I’m willing to buy them and try anyway because I have normal 318 heads and I can deck those a bit if need be. Using factory adjustable rockers from a 283 because oh my god rockers are expensive