Does welding up the stock frame make it comparable to an aftermarket frame? I'm guessing not. Does anyone know how much of a difference this makes.

figured i would bump this up instead of starting a new one.

what is the preferred method for welding. i only have a tig and was thinking that should be fine? and er70s-2 filler ok?

Personal preference.

welding it makes it dramatically more stable...with good control arms, steering box and arms and it is very good, you can run a 10 inch wide rim with the stock frame, on some aftermarket frames you can run 11-12 inch wide rims

Once you get in you will see how inadequate the factory welds are. TIG should be fine but after it's been baked and media blasted. 70 is good