Hi Rick, The closer you can get them to matching the better off you will be. On my first boat I didn't do much to make them match and had a lot of trouble matching them up. On my last boat I hot glued the deck to the form where it stuck out away from the form and the glassed the outside. After glassing I stuck spacers in the hull to help keep it's shape and did the same for the deck. In the places where the deck stuck out I pulled it together a little with tape when I glassed the inside. It made a big difference when it came time to fit the two together. No hatches is going to make things more difficult. I had one place where I had trouble matching up the deck/hull and used the fitup trick shown below. I hot glued it to the low side of the joint and drove a wedge through. A description of what I did is shown at the link below.