Assemble the frames, sheers and keel without cement and place the hull structure upside down on the building board. You may need to tape or tie things together with string.  (I used kite string.)




 
 After the frames, sheers and keel are assembled, then line up the marks on the tops of the frames with the centerline drawn on the building board.

  Now check to see that the frames are transversely perpendicular to the keel and board centerline by referring to the lines that you have drawn on the board. Note: that the frames will not be vertical to the board. They were designed perpendicular to the waterline. Also note that a 3/32" shim is needed under the sheers at the transom to level the transom. When you are satisfied with the fit and all the frames are square to the keel, now you need to cement the legs of the frames to the board.   I used Thick CA for this.