I have just purchased a 1989 Strider Club, I know nothing about sailing but intend to learn, my question is there are black covers or plugs in the bottom of both hulls, what are they??? Where do they go?? I know there are keels under the Club, do they go into that area?? One side is dry the other has a small amount of water in it's hold. Any info would be greatly appreciated, thanx, Dave G. Kissimmee, FL