Notch rudder for Drive Horn. Drill and cleco T13-03 Drive Horn to rudder. Drill and cleco 2 ribs to rudder. Still need to drill one hole for T13-04 Forward Rib on Drive Horn and install hinge T13-07 on rudder. I am going to wait until the Vertical Stab is bullt to install the hinge on the rudder to make sure the rudder and vertical stab line up correctly.