Hello Again, The cost wasn't as bad as you might think, at least in the world of tracked vehicles. The hardware, ,wheels, tires, hubs, spindles with torsion units, (same as fitted to light trailers) and the steel needed to fabricate the subframe ran me about $1100. We were able to reuse about half the old frame here and there. Spryte tracks, 68 grousers worth, times two I was able to find for $1600 for both. New belts for one side, somewhere between $1600 and $1800. As to using your existing 31.5 Super Imp tracks? Yes with no problem, but the changes will shorten your footprint slightly. This will make the machine turn easier, but you are looking for better flotation, so search out some additional grousers (perhaps 6 to 8 per side) and streach the tracks a bit. This will keep the machine from becoming nose lite as well. If out looking for tracks in the boneyards, NEVER buy a set that has been coiled up and stored on its end without close inspection. And NEVER store a set in that maner. If left on salty groound at the edge of a parking lot, the end of every grouser will be eaten away and need restoration. If left on their sides, only perhaps two or three will become damaged. I never have understood why pallets, which have no moving parts seem so hard to use or find? Lots of evenings, PB Blaster and Howes, and about $400 worth of fine thread bolts and nuts and the tracks looked pretty good. It took about 18 months, but I found a buyer for all the surplus undercarrage parts I had removed and the grousers. ( I started this project needing to rebelt my origonal tracks, so I stripped off the old belts) That sale covered the new belting. I moved the servicable used belts all to one side and put all the new ones on one side. That is another NEVER, don't mix old and new belts on the same track set. You can do the addition, I never do, If I did I'd never have the courage to finish. Don't even ask about labor. It was a long summer, filled with quiet evenings in the shop while my wife played late rounds of golf.