I don't mind drilling into interior
fiberglass for mounting and hanging. But I don't like drilling through the outer skin.
What I do is glass in a piece of wood on the flat areas. I just use the regular
fiberglass cloth, but instead of mixing up the two-part resin, I have had good luck with polyurethane glue (Gorilla Glue is the heavily advertised brand, but others work just as well).
I just cut the fiberglass so it overlaps the size of the wood by about an inch. Then I lightly saturate the glass with glue and stick it over the wood and smooth it onto the fiberglass around the wood.
This works good for patching holes also. Patch on the inside. When the glue is set up, Bondo can be used on the outside to fill the depression.
For the curved parts, I use 3/8 inch rubber air compressor hose. I cut it to length, rough it up with a bench grinder and glass it in. It takes wood screws just fine.
If you do this, wear thin gloves. The polyurethane will stain your skin dark brown. It won't wash off. It has to wear off. Takes a couple of weeks.