Radiator selection for 73 Valiant

Looking for a radiator for my 73 Valiant, fender tag shows a 26 and the radiator measures 26 inches on the core. Now whenever I search for one, the cut off year is always 1972, same thing with other parts for our cars. Its like 73 and up are not important in the classic car world.

Anyway is there any difference in a 1972 valiant and a 1973 valiant when it comes to radiators and how they mount?