Wow...Rolling shell (mostly) shouldn't be worth much at all. He should stick a regular motor in there or something, then it might be worth the 20k since it's at least a running car.
You've gotta *really* have money to blow to spend $20k on a 3000GT shell and then have to drop another $15k+ to make it into a race car. Maybe a real NHRA dragster minus the motor might be worth it

clutch, FMIC, fuel, etc. are worth a couple thou at best used and the paint, while expensive up front is worth another thousand bucks...otherwise it's a nicely done up shell that would be worth $6-8k without those extra items IMO. If you're going to try and milk the money out of something modded, it's gotta be a complete package.
I saw it when it was at GT Pro a couple of times, neat lookin car...wish it ran right when it was out here!