Radiator sizes

I got a chance to look up in my parts book. 19" radiators came with slant 6's in all models and in 273/318's starting in 69 with heater delete or heater only. It looks like some applications with a/c or high altitude still used the 19" radiator but most used the 22" core for that. There again, generally speaking, All models with a V8 used the 22" radiator and those models with a/c got the 26" core but that depends on the model. For example, I see 71 E bodies with a 318 and no air getting the 26" core if ordered with N51 option. And of course, the performance packages like 440-6 and 426 Hemi's had the 26" radiator. All of these are generalizations. My book has 6 pages of radiator applications between 1962 and 1974. and how it was done is not etched in stone.