RE: Body shops and floors
The whole replacement panel for the driver's side area under the pedals is about 3-4 square feet or so. The patch I made from that replacement panel was about 1.5 square feet. The previously rusty area that I covered with that patch was1 square foot or less. My car is getting redone at a local professional shop. They gave me the idea (if that comforts anyone), supplied the adhesive,and supervised my little project. Some cars have exterior panels bonded on with this stuff.
I wouldn't go crazy with it, but definitely worth a look, if not a try, since the alternative often means leaving a swiss cheese areain the floor unfixed, or, almost as bad, fixed improperly.