Ok, ready for some fun?

Under that sheeting near the TE there should be two spars. Make a cut between them to remove the aileron from the wing.

Now trim off the excess sheeting so you have a top and bottom spar flush with the TE of the wing and the LE of each aileron.

Next you'll need four strips of 1/4" balsa. Glue one to each TE of the wing and each LE of the aileron.

Sand them flush with the top and bottom.

Bevel the LE of the aileron.

Aren't Sig kits easy? [:@]