By the way,

those rowing machines are actually intended to catapult launch classic pattern designs with gear up!

Pete, if the wood is sealed and there's already glass on it, I would consider using waterborne primer/paint starting with polycrylic prep followed by a mix of talk/PC to fill the weave. I don't think there's any issue with using PC atop epoxy if that's what Dan used to lay the glass down. A good sanding might be in order first though.

David.