Construction begins with the tail feathers. GP has you laminate some 1/8" die cut balsa pieces together that help with the shape of the tail. Some new guys often ask, "Why don't they just cut the stuff out from 1 thicker sheet instead of having to laminate". There is more than 1 reason for this with strength being at the top of the list. Normally, 2 laminated pieces are much stronger than a single piece, especially when the wood-grain is alternated. The outline of the tail bits are made from 1/4" x 1/2" x 36" Balsa sticks. This is where I ran into a little bump. The supplied sticks could have passed for Basswood!!!! They were so dense, heavy and hard that you could not have cut them with a Zona saw. One quick glance and I knew they would be thrown in the scrap bin! I sub'ed my own stick stock that was 75% lighter (but still plenty strong) and framed up the tail very quickly. Once the frame-work is done, you are to add 1/8" x 1/4" ribs.
Pull the parts off the board and go over the joints with thin CA. Take your pieces to a perfectly flat spot and lightly go over them with a long bar sander and 80grit at first. Round off the mentioned edges (don't do the wrong ones!) and set aside.