I was not happy with the number of rivets along the top skin where it attaches to the flange of the inside cable tray. The number of rivets ( or lack of ) would have had something to do with the parachute blowout panel. As I do not have a parachute, I decided install an extra twelve rivets, six each side. So today I drilled ( between each existing rivet ), riveted and filled the twelve holes on the top skin, much better.