In my experience, there are not a lot of operations on an average vehicle that stick welding is a good match for. The thin, 18-20ga panels of a floor certainly aren't one of them.
And before someone chimes in with "Grandpa used to patch up the family OldsmoBuick every year with a Lincoln tombstone and 3/16" 6011 rod so it would pass rustbelt inspections", just know that I have spent the last 15 years repairing those fixes and they suck!
