only problem with that is its molded on, so i really dont want to do that.
Well then yer only option is to do all the work on the outside, Basically what needs to be done is you'll have to expose the "raw" fiberglass to do the repair for example say you have a crack 3 feet long and about a 1/16 wide your gonna have to grind,sand or whatever an area 3 to 4 inches wide the length of the damaged area in other word's make a little deal into a big deal.
I would find a way to get behind it because your in fer a lot of work.