When I had a Morris Marina 1,8 l TC, I was studying how to use MIG. I got the gat cheap because it had an encounter with a deer. I was able to cut out front pilars and part of a roof from othervice crubled similar car. Fair amout of fitting and welding before windshield, bonnet and doors fitted. MIG had a timer and a special nozzel for "spot" welding. Needed a lot of clamps and preparation to imitate spot welding.
I found one small industrial machine 350€, but it was big. Well over 35 KVA, water cooled and all that.
I found out that just a stone throwing distance away from my work is shop/factory that stock anything you need for carbon brushes and motor/transformet winding. I bought a metre of 25 and 35 mm2 copper rope (used for carbon brush manufacture), 10 mm silicon sleve and class fibere backed adhesive tape good util 155C.
Old isulation had taken a little hit from secondry removal. Put some tape over the core.
I was able cram 2 2/3 rounds of copper rope on the MOT. That produces 2,4 VAC unloaded on secondary. I measured less that sec partial secodary shot circuit (tried to make it short, but it buzzed and arched), primary pulled 14A and voltage dropped 230->220 VAC. Looks like this will do.
I wonder if copper grounding electrodes could be used as a welding arms or electrodes.