The headlight, are you mad, not neccessary atall mate, fitted mine years back to my S3 & it was purely wing/area adaption required with no loss on strength at all, wouldnt touch the headlight at all tbh & by the 3rd pic looks like he just hasnt shaved enough back to push headlight into the void enough.
You need some rust protector before paint & some primer, dont just whack paint onto the rough edges & looking at the pic already, seems you've already slipped with the dremel or like already on that wing area, so I'd get a local smart repairer to sort that for you.