After first spraying the hull down with a mixture of 50% white vinegar and 50% distilled water, and letting that solution dry, I sprayed the boat with a base coat of brown primer, followed by brown enamel. I used the brown as a base coat so that when I spray the final red enamel the brown will darken the red a bit.
I hope it works out as planned. I'm also planning on a polyurethane clear coat on top of the paint to give it some depth and make it more slippery in the water.