Cut a 3/8" hole in the covering at the appropriate location and slip over the dowel. You are going to have a seam at the wing center so you only have to worry about one dowel at a time. Speaking of the wing center, I couldn't help but noticing the void in the glass at the wing center. Unfortunately that void eliminates any strength that the glass is supposed to provide. I also like to extend the glass out past the fuse sides so that the wing sheeting will not get dented by the fuse sides. Under vibration the wing sheeting tends to get eaten up.