Add 2 inches to the rudder. Leave the wing alone, keep it stock. I built mine last summer, fly it with a 91 Thunder Tiger. Also cut the cheeks off the fuse and cowled it in with balsa. The cowl really changes the looks of it. Our club has 9 or 10 flying with with every mod you could think of, even a bipe for a short time. A 91 YS makes it a rocket ship. Changing the wing doesn't really seem to make that much difference that I can see, I like mine with the full wing because how slow it can ef flown. A friend had Fiberglass Specialties make him a glass cowl, but I have not seen it yet