A jig has to be bolted to the aileron bell crank in the wing to zero the aileron. A wood jig is bolted to the end wing spar, tips removed, and a zero line established. Then with jig on bell crank, small aileron push rod is adjusted until edge of aileron is in line with wooden jig zero line on wing tip. Working through the access hatch under the wing is tough. Then the long push rod from stick to aileron is adjusted until stick is vertical. Repeated on the other wing