Making progress on my Demon

Yes, just measured the opening for the radiator. 26". Mine is a factory 340 1971 Demon. I know of a 71 Duster 340 car also with 26". Typically, at least on B bodies, any AC car has the 26". My 68 Charger is 318 with AC and it too has 26" core support
Well I'll be. Wonder what the difference could be with mine being a 71 340 car and yours too. But yours has the 26 and mine the 22? I'd sure like to find out why. This has me puzzled. But I do believe with a good 22 inch radiator properly set up with a Milodon high flow water pump, 160 Milodon performance thermostat, good mechanical fan that draws well along with an electric fan to use for sitting in traffic that it should cool pretty good..