Hi Dan

Yes, as Bob say's the groove need only be large enough to allow movement of the aileron up and down a certain degree.

Taking it right back will give you 90 degrees up and down on the bench but you won't need it in flight so I only took it back enough to give me 6/8" out of the wing, I can only get 5/8" up and down now due to the alieron hitting the strips on the TE which is good enough for flight purposes.

Hope this helps.

Lee