Putting the deck back on

[fishingjoey]

This spring I decided to take the decks up for an inspection . Im getting ready to put them back down and was wondering if I should seal the
Up with 4200 or use some other alternate method that would make a good seal but not be so difficult to seal and reseal like using the 4200. As an aside I was astounded by how solid the area under the decks were. Everything appeared to be dry as a bone. The stringer foam also seemed very dry. One thing I was worried about was the way the t top was fastened to the deck. They used regular inch an half screws I would think a nut and bolt with a backing plate would be the way to go. What do u guys think?