Before clecoing the skin to the understructure, I placed bubblegum-sized daub's of RTV to join the stiffeners between the right and left sides of the rudder at the trailing edge. This should prevent cracking down the road. The skin was then clecoed to the understructure and then riveted in place. Most of the rivets could be squeezed but some had to be bucked because of the distance between the leading edge of the skin to the front spar was greater than the yoke reach in some places. Also, I haven't riveted the bottom corner rivet on the trailing edge of each side yet because of the tight quarters. Still thinking about how to do this. I will seach the RV List to see how others have done this.