If it is a balsa built up wing you can just cut new peices of similiar type wood and glue them back in the oversized hole you cut and re-cut the servo hole again to the correct size. If its a foam core wing you could probably glue in a peice of hardwood where the servo mounting plates are and screw the servo into the hardwood. In other words, no, you dont need to buy a new wing kit for what your wanting to do.