Body help/advice needed

Thanks for the input lenky, if i knock those plugs out, when i weld them shut do i put a small piece of metal in then weld or just weld the hole shut using the welding wire? If so can the entire hole be welded at once or go at it in steps to keep heat down. Holes are probably 1/4". As for the seams your recommending a seam filler and not the 3m 8115 bonding epoxy?
Thanks Rod.