Agreed ondarvr.
Munson, if you're doing a composite with plywood as the base and then a fiberglass layup with an epoxy coating I'd recommend a good quality marine paint as a finish.
Some say it's too expensive but I use Interlux Perfection on just about everything. If you are not familiar, I'd recommend doing some research into it. I find it harder and more durable than polyester gelcoat. Much easier to repair as well. I'll see if I can find a photo to give you an idea of what it looks like.
View attachment 166535 Those flat panels are just Araucoply Radiata Pine Plywood. It's not marine ply. Would I build a hull out of it? No but it's fine for my flybridge. Those flat panels you see have been installed for over a decade and look as good today as they did when they were new. The schedule was two coats resin as a sealer. 4 oz cloth. Three additional coats to secure the cloth and fill the weave. Two coats Interlux Epoxy Primer and three coats of Interlux Perfection. When ply is sealed that well you'll have no problems.
Here's a little different profile of a panel done as I just described. Perfection can be "rolled and tipped" to give a very smooth and shiny finish. This photo shows it just rolled but not tipped. I like a little matte finish on my panels so I don't go for the super shiny look.
View attachment 166536
Good Luck and welcome to the forums.
MIA