Do all A bodies have overheating problems?

OLDMANMOPAR posted something interesting some time ago, and "it fits" what mine was doing. The original 273 "round tank" was in front of a 360, later a 318. It would overheat some worse on the highway. I was at a loss. A rad shop said "it flowed fine"

OldManMopar claimed that the thermal cycling over the years can crack the fins loose from some of the tubes. It can flow all the water in the world and won't "radiate."

I'm CERTAIN that was my problem. As a 'try this' I swapped in a two core slant six rad out of a later car and the change was immediate and enormous.