Here's a thought...buy a set of Proline Velocity 6 rims with your choice of tire (Try Maxx Mashers. Get your chain together, and instead of trying to make snow chains like on a real car, think of making a snow tire or a hybrid snowtire/chain tire. Here's the thought. Take some chain and loop it through the rim and around the tire then hook it to itself (like a bracelet around your wrist--instead go around the tire, through the rim and back out.) You could make 6 such bracelets per tire, and use the spokes of the rim to keep them separated. Then when the season is over, just spread one link on each of the six bracelets and remove them. You now have your off road tires back. Just an idea...
As for making a true snow tire, you could get a set of Maxx Mashers and try this, but I think that the Mulchers would probably work better. What makes a snow tire...good tread pattern and the addition of steel studs imbedded in the rubber. You probably can't do the imbedding thing, but you can take a good set of rivets and create your own studs by passing the rivet through the tread and fixing the rivet to the inside of the tire so that it doesn't come out. You'd better find some light weight stainless or zinc rivets (the kind that don't rust), as this will make the tires a little heavy.
Just a couple of ideas for your creative nature...good luck...