I drilled three holes to mount the transducer. It appears it just went through the fiberglass into some foam. I don't know if the fiberglass is strong enough to hold the screws? I am very worried it will leak if the mount gets loose or the screws get loose. I have been researching this issue.....one guy says to oversize the drill holes, and fill with epoxy and then drill the pilot holes through the epoxy? Would any kind of epoxy work? How big should the oversize holes be. My boat is a 1997 Dynasty Elan 180......I am trying to mount it on the drivers side just below the exposed u bolt for securing the boat to the trailer.........