I'm making this up I type 'cos TBH I've never tried to fix an ally box as thinly made as those nasty things, but.....
Look for a solid former that's as close to the interior curve as you can find......a bar, a tube, whatever.
Use heat, and a large flat surfaced bashing device (there's probably a technical body repairer's name for that sort of hammer, but the idea is sound) to gently flatten the heated outside surface back to the forming surface's shape
Add chemical metal to the inside surface, allow to set, assuming that's a hole I see there.
Sand down exterior using sensibly increasing grit numbered papers., going back to the forming part as and when required.
Get the best possible surface you can, or vinyl wrap both boxes if it's not good enough for you.
Don't wring your hands over the minor blemishes once it's done.......it's not 'damage', it's 'Character'
