Mounted the forward attach plate by carefully marking and aligning the plate's centerline to the spar's adjoinment line. Note the plate's top half has a 'jog' to the aircraft's left. This means the vertical stab's leading edge is offset left a fraction of an inch...a standard feature to help address P-factor and centrifugal force from the propellor.
With the attach plate clamped in place, I set the vertical stab atop the horizontal stab's spars and clamped, measured, reclamped, etc.
