Value and worth is all relative. Your machine's value currently is basically the body and engine if the tires are shot(just my opinion). If you were to part it out or sell it outright I would think you would only get $1000 in a good day. A t-20 can be had for very little if you keep an eye out. There are several ways to get one too. I traded $200 in tires for one from a member and I think a gave $175 to another member for the one before that. Both were good deals, and I would expect to pay more like $250-$300 for a tested but not refurbished used t-20. Member MaxIVMark got his last t-20 by buying a parts max II that was lacking a body or engine. I bought the frame off of him for a custom build, so I think he has about $150 in the tranny. Buying a busted up machine for a few hundred can get you some extra parts to sell or barter with to cheapen the build. All that being said, once you have a t-20 in it and good swimming tires you should be able to sell it for $1500-$2500. If you sell during tax season, you could even get as much as $3500-$3900. I do believe a member got somewhere around that last year for a really nice superchief. The real value of the conversion is in having a reliable rig. I use my Attex 450 on trail rides, and although its more than 30 years old, I don't seem to have any more trouble with it than any one else. Also, my machine isn't depreciating like a quad or side by side. I feel I purchased my machine after the market bottomed on AATV's. People tell me you used to be able to get good running machines for a few hundred bucks years before I got into the hobby. Now if you see a complete but beat machine for less than $1000 they seem to sell quickly. All things considered it is well worth upgrading your rig and using it for the next 5-30 years. If you build it to use, the value is there.