WOW! I didn't know that they still used that method!!! Ok heres what I would do. Measure from the centre of the wing joint 2" out from the left side of the wing and draw a line all the way around the wing. Now do the same for the rigfht side. One of those felt perma markers with the thin tip will work well. Then very carefully with a sharp exacto knife remove the covering from the centre out to the 2" marks. Now use 15 minute epoxy to join the wing halfes together. Make sure the top of the 2 wing halves are touching until the epoxy has cured. Now turn the wing over and you will see a gap between the 2 wing halves. Make another batch of epoxy and fill up the gap with the epoxy. Get some 6 to 8 oz. fiberglass cloth. and cut the cloth 4" wide. Use 15 minute epoxy worked into the cloth to go around the wing. I would do the top in 2 stages and then turn the wing over and then do the bottom the same. Sand the fiberglass job until its smooth and then recover the 4" wide section with moncoat. hope this helps.