Fiberglass repair

mbrower wrote:
A picture of your damage would help. Small damage should be no problem for a competent body shop. If its fairly large and the structure of the side wall was intact, I would laminate the whole wall with a new fiberglass skin. I would remove any windows and trim/molding, smooth out the existing skin with 280 grit D/A paper, fill in the missing fiberglass with a mixture of resin and chopped glass if small. Larger areas I would repair with fiberglass cloth. Once cured, I would sand smooth. I would then attach the new skin with a quality type of waterproof contact adhesive. Replace all the items that was removed and any graphics and it should look brand new and durable as well.

This is only a suggestion as I have never done this type of repair. Having said that, I have done body work for 30 years and all types of fiberglass repairs and this is how I would do it if my own was ever damaged.

You can buy the skin and contact adhesive here

This is very good advise. If I were in the same situation this is exactly what I would do. I have patched small holes and dents before with plastic body putty and painted to match with excellent results, but due to the size of your damage I would do exactly as mbrower suggests.