Putting on the Long pieces (longerons) The ribs are in place and they are screwed down to the floor, NO glue yet..... Take a strip hold it against the center rib, being sure that it will reach past Both ends and mark it for the screw that will hold it to the rib. Drill the hole and, lining it up to the top of the rib drill a pilot hole for the screw, ( I used sheet rock 1'3/4" screws) Put a screw in to hold it in place and go to the OTHER side of the boats and do the same thing. As you do each rib , be sure that every rib is 90 degrees from the floor and 90 degrees from the center line. Do one rib toward the bow on each side, then one towards the stern. A way to make it easier is to put in JUST the center screw and then bend the piece around the ribs at the gunnel and tape it into place for a few days. It will take a "set" and make it much easier to drill and screw if you are working alone.