I think gwp is wrong. The area is over 1 square foot. That's a large area to fill with epoxy that way. Besides, there is little strength to epoxy without fibreglass imbedded in it. And this will be under a mast so it requires strength. You will have to paint, but it's easy to get a fair surface. Just build it up layer by layer (1708 biaxial is about 1/8" per layer I think) and when you are almost level with the deck surface, sand and squeegie a fairing coat of epoxy mixed with fairing filler (West #407). sand and refill any low spots with fairing again until there are no more low spots. Sand lightly and finish with a coat of straight epoxy put on smoothly. Then prepare for the paint you choose. It isn't hard to do it just takes a bit of time. If you can read instructions you can accomplish this.