Yep, it's as simple as that. You can add a flap servo behind the aileron servo and run nylon pushrods to the ailerons or put the flap servo where the aileron servo goes and make servo mounts in the wings for the ailerons. Also, the 60-size has you remove about 3" from th outboard end of each aileron and glue it to the trailing edge near the wingtip. If you add flaps, skip this and extend the aileron out to the wingtip block.

Another mod I strongly suggest is to move the retracts out by one rib bay. This makes it more stable on the ground and allows for slightly longer landing gear if you need the prop clearence.

Aside from those two mods, do not make any others. This plane flies so good and anyone I've seen make any mods to the airframe design has only diminished it's flying capabilities.

Also, don't look to save weight in the construction. Many of us have found that the US handles a little extra weigh better than making it lighter. I like to fully sheet the wings for a cleaner look and, as I said, it actually flies better when it's a little heavy.