Gotta agree with Mike East. I've used a dial indicator to get elevator halves set right, but the two sticks method works too. I am mostly experimenting around with the dial indicator to set incidences, thrust lines, etc. I use it to mark the fuselage for a base line for installation of stab, wing, and engine. But, I agree that the final decision is from the way the plane flies. You can measure all you want, but your loops may be corkscrews until you do the final adjustments.