When we did the major chassis mods on my son's HiLux we hired a big MIG from Coates because I only had a little 130A one then.

I've now got a 200A one that is good for anything I can throw at it, cost $1K on special but in reality is far bigger than the average home handyman will use most of the time.

The little gas bottles are useless, nothing smaller than a D cylinder with proper regulators and gasless cored wire is really only for windy outdoor use on the farm and makes far too much mess.

Note: don't weld in multifocals unless you want to weld in circles or transition lenses with an auto darkening helmet ( no need to ask how I know this ), cheap readers from the servo or chemist is what you want

Edited to add: flash burns hurt so cover up properly and use proper welding gauntlets