My 14ft Klamth does not have a drain plug, without a garage or carport, having to rely on a cover still allows some water inside. I want install a drain, and a garboard plug was recommended. A 1" hole, and then 3 smaller holes to secure the plug to the transom. I drilled the 1" hole, but am now having second thoughts. I/m worried that I won't be able to seal up the 3 smaller holes enough to prevent water entry. Any suggestions for a better solution?