Aluminum road signs get hit and mangled regularly in my region, and there is a temptation to grab a chunk of whatever tiny bit remains flat, chopping it out of the wreckage with a cordless jigsaw, as it's at least .080 thick, of a very corrosion resistant 5000 series alloy, but you're depriving the road department of the value of the scrap and the reflective coating WILL NOT come off, not with heat, not with chemicals, thus forever branding whatever small bracket, shim, or spacer you might think of fabricating as sourced by theft.
Don't do it.
Don't do it.
