Steve,
I have studied the snot out of it (them), but have never used the one from HF. I have used another brand...expensive commercial one. The true test of the spot welder will be the combined max thickness it will zap together. The 220 volt version will obviously have more capacity than the 110 volt version...but, dragging around the larger cord, and rigging up the plug could be bothersome.
Examine the two parts you intend on welding together...my guess is that their combined thickness will far exceed anything either spotwelder could do! The sheetmetal on these trucks really isn't "sheetmetal" in the true sense of the word. As I recall, most body components are about 19 gauge...that's ONE piece. If you want to stick TWO of these together, your going to need a big mama!
Stuart
