I have a 1976 15ft Hydra-sport "hydra-flight" bass boat and I'am in the process of making a transom from seacast, but I need to fill in a ole so I can pour in the Seacast without it leaking out. Under the deck, below the splash well there is a strip of fglass missing. I tried glassing over it , but with the 90degree angle the sheet of fglass just fell off .<br /><br />Does anyone have an idea of how I can close up the hole(on a 90degree surface). Hole is 13 inches long, 4 inches thick.