I used a poly glue, Elmer's Ultimate (now called nano, and similar to gorilla but half the price and thin like syrup) to do my king kobra wing join. I used masking tape to line it up and pins in the leading edge and trailing edge to keep in lined up. This stuff is crazy strong.

I recently cut out the servo hole in the wing for the retracts and this disected the wing join. OMG it the foaming ultimate glue penitrated the foam by 1/2" on either side of the wing join and was a B****H to remove the glued foam. WOW!! I love this stuff.