Well in all honestly. It gets someone a cheap set of axles. And a parts truck. Not to mention if it was a 5-speed! Maybe he has the old parts. If he's stupid enough to swap a gas engine into where a diesel used to be, maybe he's stupid enough to sell all the old parts dirt cheap too.
Sounds like the engine went bad and he went the cheap route and just threw a gasser in it to get it sold. Doesn't really make sense though since that truck with a bad cummins would probably be more profitable. But im guessing there isn't a big market for people wanting a cheap diesel to fix up like there is down here.
Wasilla is the warm part of Alaska, heck they hardly get any snow, i buy similar trucks like that for $500 bucks, cummins powered ragged out dodges not running still sell for $3k here.