My daily driver has a few rust holes in the floor pans - its a 90 Dodge Daytona which which I'm trying to keep another year or two. I put some POR-15 on the bottom to lock the rust, but am unsure how I want to patch the holes, which are about 4 x 6 inches. The rug will be removed and the holes patched from inside the car - I was thinking of using fiberglass matt. Should I just POR the matt down, or stick with epoxy resin? If I do the traditional fiberglass/resin repair, can I POR the metal first, or will I need bare metal to bond to?