Per the instructions I trimmed the exess off the flanges of the rudder brace and clecoed it to the rudder horn (R-405PD). I then clecoed the aft flange of the rudder brace to the bottom rib (R-904). When I went to rotate the forward flange to line up the holes in the spar, the rudder horn interfered with the rudder skin. The rudder skin reqired trimming back to the forward edge of the flange on the bottom rib. I also had to radius the top forward edge of the rudder horn to nest into the inside bend radius of the bottom rib flange.
The instructions call for match drillng the rudder brace to the rudder horn, but the holes in both parts already exist, so I just final drilled them to #30. The instructions do not mention match drillng the rudder brace sides to the bottom rib. I thought these might be drilled in assembly later with the rudder bottom attachment strips (R-918), but the plans show the strips ending just aft of the brace, so I went ahead. Before match drilling I marked the rib/skin hole positions on the brace and removed the brace to check edge distance (minimum 3/16). All were in spec, so I match drilled the brace sides through the skin and bottom rib.
Skin interferes with rudder horn.
Skin trimmed back to fwd edge of rib flange. Rudder brace drilled and clecoed.