The S3 Land Rover chassis seemed to be about 3mm thick last time I hit my head against one. That'll require at least a 130 amp welder.
A Clarke 130EN would work with Land Rover chassis using flux cored wire which is cheaper for small jobs but less easy to use than normal wire and a shielding gas bottle. Still perfectly acceptable results though once you get the hang of it. The only real downside to that welder is it will struggle above 4mm.
Yeah 2mm standard and 3mm heavy duty on Landys. My 130 amp did the job on them but better with a bit more I think. That is one of the reasons I got my 211 Portamig. I aint struggling on chassis stuff now !
Alex
I know this is a mig welding forum, but if the plate is that thick, why not stick weld it? Better results on slightly rusty/older steel and perfect welds with a much lower initial cost?