My 1986 H31 has developed a leak in the holding tank, midship below the V-berth. Previous owner attemped to repair by placing a metal screw in the hole. I was thinking of openning the holding tank, cleaning out and effecting a fiberglass repair (the tank appears to be constructed of fiberglass) After completing the repair, I thought it may be advantageous to coat the interior of the tank with several coats of barrier coat epoxy to prevent futer leaks. What do you think of this idea or can you offer any other suggestions.