On my first S&G, I put the deck on single handed and wound up with a 1/2" gap (widest point) between the deck and front bulkhead. I was expecting the boat to get some pretty rough use, so after I cut the front hatch, I reached in and used cardboard to make a pattern of the gap. I cut the "patch" out of plywood, fitted it and epoxied it into the gap. I then fileted and taped over THAT, just to be certain. It may have added a few more ounces, but I had peace of mind that it was solid support for the deck and wouldn't be leaking anytime soon.