I have some rust holes in trunk area that i'm gonna use filler or fiberglass to repair. I want to put por 15 over entire area afterwards, does POR 15 stick well on filler or glass? thanks

Actually, the Por company makes and sells their own fiberglass mat material that works well with their product. They sell a trunk floor repair kit, but I do think there is a limit on the size of the holes. How big are the ones in your trunk? If the holes are larger than dime size, you'll just be wasting your time and money.

However, they recommend using silver Por 15 and embedding the fibermat in it while it's still wet, and then painting over the top of it again. Then they recommend Por Putty over the top of the mat after everything has dried for four or five hours.