The rudder trailing edge needs to be held perfectly straight when bonded together before riveting. Bought a piece of 1" x 1"x 1/8" aluminum angle to use as a jig. I programmed my CNC router to duplicate the rivet hole pattern in the trailing edge skins. Very acurate and easier than trying to "match drill". I plan to use 3-M VHB "Tape" to bond the trailing edge together instead of the old "Fuel tank sealant" method.