I sanded both boards on a 40-80-120-220 schedule. Then I put two coats of Rustoleum Matte Enamel to fill in the residual scratches.
These both came out nice. There are some bubbles here and there, and the reinforcement block area leaves a lot to be desired, but all of that adds to the homemade character. I'm glad to be finished and can't wait to get these wet!