Or tractors or anything in the utility class of farm-ranch type vehicles...??

Close but no see-gar here. At one point I built a propane-only Suzuki Samurai with a rebuilt 1600cc engine. Good times. Man that thing would go!

Definitely no Alaska weather challenges here though. And no rust

I used to be a roofer. We did a lot of flat roofs putting down a membrane that was laid using propane torches. When it got below about 10F, we'd have to cover the bulk tank with a tarp and put a heater under it or we couldn't get enough pressure to run the torches. I suspect that when using propane at -20 you'll run out of power real fast.

It would be nice if we had locally made propane that was cheaper.