These sketches are admittedly crude but perhaps with a bit of explanation.
Upper attach, the gap cover gets a piece of 3/4 angle riveted on the aft rear such that it falls about 3/4 from the rear spar. This angle should have a 10/32 nut-plate facing aft. At the rear spar a piece of 3/32 - 1/8 aluminum is fabricated such that the rear spar now consists of the each of the outer and inner spar attach and this plate. The rear spar bolt captures the new plate. The plate has a hole drilled for an AN3 bolt to pass just above the center of the rear spar plates.
Lower attach, at the aft end attach the gap cover to the lower skin with <6> 8/32 nutplates they should line up with the area around the aileron control rod.
Assembly, attach the lower side with <6> 8/32 machine screws, at the aft end of the upper side of the cover place an AN3 bolt through the fabricated plate, capture the angle with the nutplate on the cover and tighten until the cover is acceptably tight (this is adjustable so the cap cover will most likely not bottom out on the plate).
Attachment:
IMG_4449.jpg [ 1.67 MiB | Viewed 10354 times ]
Attachment:
IMG_4450.jpg [ 1.97 MiB | Viewed 10354 times ]