Bondo Metal Filler vs. Fiberglass

[Karateboy88]

^No need to bash someone you don't know.

Taking a closer look at those pictures (the one with the wheel hub) even the subframe and under chassis is rusting. That much rust is an issue. I would actually worry about the more structural stuff than the cosmetic bs. Get a grinder, some wire wheels, and some flap discs to completly clean all of the rust of and then paint on some underbody liner or truck liner. I would do that if you want to save it before it really gets bad.

I think that I am going to sandblast 90+% of whatever you see in the wheel well- it's a text book example of surface rust.