Since you are using the connecting shafts between the airlerons, go to page 17 of the manual. Step #4: Do not use their instructions! The distance to the rear edge of the control horn is 7/8". This eliminates the binding you'll get using their instructions. I got this from R/C Report magazine and it works beautiflly on mine and several others at my field.

What engine are you planning on using? I have a G-23 in mine and it's a great match for this airplane. I can loop from level flight. Also using this or a G-26, you won't have to build the weight box and add all the extra weight to get it to balance.