Although I have not needed POR-15 on my DeLorean frame, my wife's Nash metropolitan needed extensive frame TLC. I researched the available products and chose POR. The paint over rust is just what the name implies, you need oxidized or etched metal for it to bond. It is amazing stuff that dries to a ceramic hardness. The rustier the frame the better it works. There is even a putty available for larger holes but is not structural enough for strengthening a frame. If you use this stuff, use rubber gloves because it DOES NOT come off the skin. It has been on the Met for two years now and still looks like new. Also remember it will not stick on the epoxy frame coating on our existing frames. Cecil Longwisch #10663