Supra: unlimited potential, a solid platform to build on, and a good market to build parts for.
Volvo: comfortable, decent fuel mileage, dat 5cyl sound, and relatively low-maintenance.
It doesn't sound like you'd really be utilizing the spool gun so I wouldn't really look at that as a selling point. As Ross said, that'll be small for frame work. I think you can get a better welder for your money if you shop around some, maybe even buying brand new.
Someone should close this thread to alleviate the loss of additional brain cells. Some of you need to seriously step the fuck back and examine your standing in this.