Finally got the alternator installed, and got a break in the snow today, so I was able to let the fan run for an hour. It got cold and dark, so I didn't go any longer than that
It otherwise seemed to work just fine; no smoke from its controller, or turning off by itself.
I think at this point I just need to finish up the circuit board and start moving forward with building them.
If you ever find yourself in a fair fight, your tactics suck.