nason is a great product for someone who has never shot paint before very forgiving and great results........

No 5200! I'm a fiberglass guy. If you put 5200, when you call the fiberglass guy, he will need to take it out before thue glassing, and will ave a hard time. The easier and safer, is just get polyester filler, any kind of polyester filler, and just filler it up with a spreader. For a smooth aplication, you will need to grind the area and edges prior to the filler. If not you can sand them to with a really abrasive sand paper like 60 grid.
Now, that is not an expensive repair to do, don't worry too much...
good luck