Once Tuff Stuff gets back to me, I'll probably just buy the high amp alternator. Then I can do a proper test here. My charger is only 10A, which still may not be enough with the truck to power it

The heat I was wondering about was the heat on the fans controller from sitting on the hot radiator, not my board. The microcontroller I got is good to 300*F, so it should be just fine under the hood

I was under the impression that the fan I have is a (damaged) OEM Mercedes one, and that it would work fine with a constant 12v? And if so, I'd prefer to test on a fan that requires the PWM.