Re: How to glass
Coating with epoxy may be a good idea, but I am not sure why you would need to coat an internal part with fiberglass, so long as the boat was designed without it.
If you do want to coat it, the lighter the glass the easier it will conform to complicated curves. So instead of a heavier glass try switching to 3oz or so. If its really weirdly shapped you can go down even further. The lighter the glass the easier it conforms, but the more layers it takes.
If you want to do the best job possible, after all the glass is layer up wet, encase the part in a vaccume bag, and pull down a reasonable vaccume. This will help apply preassure evenly across the part, and press the glass into complicated curves.