It's best to build a 'tiller' so that the servo connects to it via an adjustable link. The tiller takes the tension loads (which shouldn't be much). By having multiple attach points on the tiller for the servo's link you can adjust the throw and get better mechanical advantage. It's easier to match the width of the hole from the horns to the tiller, too. Servos connected to the flying surfaces may give too much throw unless you adjust travel rates. The throws are smoother in flight if servo connects outboard to where control cables do. If a servo needs changing it is easier with a tiller setup. It's easy to duplicate the rudder bar in a scale fashion so the control runs will be more accurate. What DVII are you going to replicate? I have one of these BUSA kits and have a Proctor kit on the way.