I have a whaler that has the stainless steel railing around it. The screws don't grab anymore. I'm assuming there is wood behind the fiberglass that is rotten. Any chemical, anchor or technique to make the screws hold tight?
There is no wood in your whaler, just foam ......(or at least I'm about 99% certain.). I would overdrill the holes slightly and fill them with finely chopped glass cloth mixed with epoxy, then re-drill new holes.