The Text Manual says to "tape" the leading edge of the rudder trailing edge before transfer drilling... The overlapping leading edge surfaces that I would be drilling did not seem to be supported very well with just tape. So I clamped 2 x 2 s on each side of the leading edge to hold the edges on a straight line between the root width and the center width (repeated for the center width and the tip width), and then clamped a length of 3/8" aluminum U-channel inside the trailing edge. This arrangement held the overlapping surfaces straight and provided support for drilling. It worked like a charm!
