So we have been doing a lot of fiberglass work on our Boler
, and we needed to patch a very larger area where a previous owner had put a hole in the back and installed an AC unit. I hit upon an excellent idea to make a patch for the hole. I put a call out to craigslist, looking for a fiberglass tub surround that someone might have pulled out during a bathroom demo. Someone called and said they had one in the dumpster that we were welcome to come and get. It was perfect! My husband measured the hole, cut a piece from the surround, and fiberglassed it in place from the inside (we have no interior covering at the moment). Filled the cracks on the outside with a fiberglass putty stuff I think (might have just been bondo). It looks fantastic and was so easy! Much easier than trying to make a patch that big from scratch. This works great if you have a large hole to fill in a fairly flat area of the shell. I can take some pictures tonight if anyone cares to see them.