This is how I do it. Just wondering if there is a better or different way. I like to mount the arm on the servo at the center of the travel arc of 60 degrees both directions. I start out by using the neutral point of the servo arm being parellel to the hinge line, say it's the aileron. Then by moving the arm 60 degrees one direction, I make a mark on the wing where the pushrod will connect. Move it the other direction and make a mark on the wing at the other spot. Now draw a line between the two dots and down to the hinge line. This is where I mount the control horn at center. Is this how you guys do it? I am trying to get the best mechanical advantage.