Rudder cable exits. I did a straight line measurement and from the rudder servo to the horn location its about 2 1/2 inches from the cutout at the rear fuselage. I marked two lines at this spot, cut a slot with the dremel, cleaned the slot hole with an exacto knife, cut a couple of nyrod inserts and glued them in. The nyrod inserts are important because they will keep the cables from wearing over time at the exit point. This alleviates an issue if you fly over 200 flights.