I've built 3 of these over the years and still have the last one I built 9 years ago. I used 1/16th aircraft ply as doublers where the cabane struts attach inside the fuse (don't know if you can retro fit that after the sheeting is on) and on the wing ribs where the outer struts are attatched. The wings are a very light build and seem kind of flimsy but after they are covered and the plane is assembled they become very strong. I've been flying mine with a YS 120 the whole time and is one of the most fun easiest flying planes I've ever had. Good luck.