Layed out the cut / drill pattern on the control plate. Used a single flute router bit to cut the slot. Verified it fit tight on the pin of the flap control arm, and would slide to each end. Layed control plate on inboard rib and used a sharpie to mark the pilot hole and slot locations. drilled 1/4" holes at end of slot in rib and used a round file to make the slot placed control plate back on rib and drilled rivet holes to final size
