Just a few weeks ago I discovered a small stainless steel screw at the very bottom of my transom was a drain plug for the entire area underneath the deck of my 14' fiberglass runabout. After I removed the screw, I got about 30 gallons of water to drain out. I am attaching pictures of my transom so you can get an idea of the location and size. I have a regular brass sleeved drain on the right side of the picture that is above the deck but the small hole in the very bottom middle is below the deck. What should I replace this with that will be a better solution than just a screw with a little sealant around it? I don't have access to the inside of the transom to put a plug like the one above the deck. Is there a good plug that mounts from the outside? Thanks for the help.

