Solder two short insulated wires to bridge the connections to hard wire your powered speaker to either Right or Left as desired. Finished result should look like the photo, (Right powered speaker selection) only cleaner, with no hastily added electrical tape shielding, because you are better at soldering than I am.

Do make sure your wires lay pretty flat to the board so it won't get in the way when you slide it back in to the speaker casing.

Optional Method: As a few users noted, placing the bare wire from an insulated wire on the pins and soldering them down ALSO WORKS. This method lays more flat, but really only works when doing the right speaker formation since they are parallel lines.