ok - Similar project at the base, but I'm using the existing stanchions and lifelines. I made G-10 backing plates that will be bonded underneath the deck. I shimmed the G-10 with smaller pieces of G-10 by the deck seam so the plates are flat on the bottom. On the top, I'm using white 1/4" polypropylene sheet that is cut to fit under the stanchion bases and extend out an inch to help spread the load. I'll bond the polypropylene to the deck with 4200, fasten the sandwich with the G-10 epoxied below decks until the resin and 4200 cures. Once this is done, I'll use silkaflex under the stanchion bases, loosely draw down the stanchions with the fasteners till the caulk cures, then tighten it up. The G-10 cost me $75 and I got the polypropylene from a friend for free.