Fiberglass Topper Repair

Long story short, my topper was off to fix some of the water sealing issues on the bed rails and my dog wrapped her leash around the improvised sawhorses and knocked the whole thing down.

I'd like to fix/patch/repair/whatever this giant 5” bite out of the bottom rail.

What does the hivemind think? The whole thing is going to get a wrap after this is fixed, so I'm not worried about paint, just texture/smoothing. Where can I go to get this fixed well enough to wrap?

 

It doesn't look like it's in a structural area. Do some research on youtube on the boat repair videos, you can fix it.