If it is wider than a single car garage door then you probably have the wide track version called a Trac Master or Snow Master (early versions were called Trac Masters, later versions Snow Masters). The Snow Trac and the Snow Master are very similar machines, built from 90%+ the same parts. The obvious visual indication that is most striking is the much wider tracks of a Snow Master.
If is was me, I would toss out the VW engine and put in the Suburu powerplant. The advantage is you get a compact water cooled engine that can provide heat for the cabin with the little Suburu boxer engine.
One of the other members here, a guy named Larry who posts under the name ROUGHWOODS, did a Toyota engine swap and has some pictures here (maybe in the photo gallery?).
Also a guy named VILLI who lives in Iceland posted some photos of a Snow Trac with a Suburu engine installed. It was a very clean install. Villi doesn't own it, the unit was for sale and he posted the photos. It was probably the best engine swap I've seen.
If you want to stick with VW, then look for a thread about ARLOWs Snow Trac. He is in British Columbia and did the best upgrade/restoration I think anyone has seen to date.