Semi-related... I had a 1988 F150 that had cooling issues from the day I bought it new. Ran fine, snowplowed with it, but on the highway it would heat up even in the winter - which made no sense when plenty of air was flowing over everything.
One winter, after seeing a big rig with a cover over the radiator, I figured I try it on my truck (I know, doesn't make sense since it already ran hot, but I was younger). So, zip tied a piece of cardboard over the front grill, and...
It ran cold! Engine just barely warmed up, and it ran the coolest since I had owned it. Far as I could tell, it had a bad / wrong temp thermostat installed, which wouldn't kick on until almost no air was cooling the engine - then it "over cooled" the engine.
Sometimes you just don't know until you experiment!