Rust above Gas Cap Door

I have a bad rust spot above my gas cap door, and I am thinking about doing something about it in the spring. I have never done body work before but I think I have a decent understanding of the prep work I will need to do. I am not expecting a professional level finish, but anything will look better than the rusty paint bubbles and flakes that are there now. Main thing is I want to stop the rust from spreading. I am thinking I need to grind out the rust, clean the metal with MEK, apply some POR, or the like, fill in the hole(here is my biggest question), then sand, prime and paint.

So, do I try to lay some fiberglass in the hole, or use Allmetal? I am guessing the hole I will need to fill is going to be about two inches high by three to four inches wide.

Oh, I have never welded, and I don't have the gear, so that is not really an option. I also do not want to pay to have anyone do this, since it would be way too much to spend on a 16 year old heap.

Thanks,
Tim

It depends on how large the hole is. If it is small then you can use bondo. If it is larger there is fiberglass bondo, that has strands in it. If it is even bigger then figerglass. I would suggest cutting out the rust. If you want to make sure it will never come back that is the only thing to do. If there is a hole there is more rust inside that you cannot see. You might be able to access that area if you take out the spare tire and the trim behind it. There is a metal support that is bolted on that can come off. You would have to really fish your hand up there. But that would be a go place to put the POR15. I personally have had alot of trouble with the stuff. If it is not perfectly clean it will fail. And since that is a difficult area to access it could be tough to clean.
If it were me I would cut it out and weld in a new piece, but you already stated that that is not an option but it is the only real way to make it last.
Can you post a picture?

K

I guess I won't really know how bad it is until I start grinding it out. The paint is bubbled up and there are flakes of rust that I could pick off with my finger. I will see about borrowing my dad's digital camera for a few pics.