Deck to Hull fastening....
I have taken what would be a screwed on deck and bolted it where I could. first I removed the rub rail then pulled as many screws as I could reach from the inside. Bolted with as large of flat washers and locking nuts as I could bedding everything with 5200.I did the same when the rub went back on I must note the screws were loose in several areas not bad but in a bad blow it could be a problem.
If you do this make sure you mark with a piece of tape or some thing where the holes for the rub rail are or it can be a bummer having to take the rail back off to get a screw out.The boat was tight after that.