Okay Maxx, here's the skinny!!!!! ARF's generally have the cutouts already for servos. You don't really have to cut anything up.
Just put together the rubber grommets on the servos. Follow the ARF instructions for servo locations. Then, drill 1/64 holes and use the servo mounting screws. Hell, my rottweiler Brutus can do that and he rides the little yellow bus to school every morning!!!
And, you would line up where your pushrods get located in conjunction with the servo. Then, add your control horn and line them up with the pushrod. Drill 3 to 4 holes for the control horn and voila! You gots a controlling surface!!! Best thing is just take your time. Most trainer ARF's take newbies into consideration when you are putting them together.

Dave...