Here is a pic of how to install the servos, horns and rod.
The horn must be on the edge of the aileron hinge with the hole that the control rod will be in centered directly over the hinge line (crease).
For the control rod, use a Z bend on one end and leave the other end straight.
Use adjustable connector for the straight end of the control rod like Du-bro mini E/Z Connectors
Once everything is installed, bind up you radio to your receiver and get all of your servos centered up. Then center you surfaces and then you can tighten up the E/Z connects.