nice work! i'm envious of the sandblaster, i could have really used one of those for similar projects (also from that same day, go figure). I guess you have no way of getting to the backside, but i had great luck with a copper bar behind the sheet to help with the welding.
Tim M Hovey
1950 cj3a: FJ60 Axles, brakes, and steering, Willy's
sheetmetal and a Buick engine, held together with
metal from the scrap yard glued together in a garage in
Louisville and dragged around behind a F350 Diesel.