When I had the P-51 (I have since sent it and whatever parts were left to a good home to try and improve and Frankenstein the plane) I too had problems with the ailerons and also the gear that is on the motor. Gluing the gear onto the splined shaft with some CA will help, use the thick stuff or the gap filler one, but it will eventually come undone due to stress or a rough landing where the prop and the shaft suffer. As for the ailerons, look a little closer to the wires, I had problems with rusting, and you may too. Landing in grass or weeds can introduce moisture to the exposed wires. If you have a Guitar or are near a music store, get some guitar strings that match the size of the current wire and replace it. The higher nickel content of the string may be a little more resistant to corrosion. I was going to try it out, but the plane decided to land before I wanted it to.
I love the way the plane looks, and feel it has potential, but as always, Parkzone takes the cheap way out instead of going that extra effort. Do the best you can with what you got.
Keep your eyes open and Glacier Girl may have some mods to this classic so that you can really fly it!
Steve