3/4 double sided sticky tape from your local hardware store. get all the old stuff off the hull, get it clean and pretty, then stick the double sided tape to the hull part, don't worry much about the top-side, just run a wire brush around that half, get it clean, then take a spray buttle mixed with a couple spoon fulls of dish washing liqued with about 12 oz water, spray it on the top-side and the hull side, pretty good, then set the two together as soon as possible, 10 minutes or so, alligning the screws to the stern first, then a couple on the bow, that will give you time to set in all the other screws, when you get them all in, then take a break, open a Bud and give it a few minutes, then tighten them all up.
If all the screws don't want to tighten up, the go up to the grocery store, get a bag of them shyskybob sticks, stick them in the hole with a tad of super glue added, then the screws will tighten up like ... super glue.
I use a 1/8 "ice pick" looking tool to align the screw holes.
edited :
just realized you done got it togther, nothing better than 3M 5200, get you some rubber gloves, clean the surface's, spread it on the seam with your fingers all the way around the seam, most important of all is the seam around the stern, use it there inside and out.
