Dgas56, all of the info given tells you to repair from both sides if you can, and to add mat/fiber to the mix. I am a fiberglass rookie, too, and I am learning as I go. Your question was can you use resin alone to "glue" the damaged spot back together, and the answer is "No". Resin alone is quite brittle and it will not be a lasting repair. You have to have new fibers in the mix for strength, using the resin to glue the new fibers into place like the aggregate in concrete - mortar alone is not so strong, but it glues the rocks together.