My reply wasn't directed at you, just this thread in general and all in good humor.
You've got it. You only need 1 template and it doesn't even need to be an airfoil. It just needs to sit on the wing in the same position with identical reference marks across the front and back. Doesn't matter where, they are just for reference. Clamp the tube to the template edge and let the water settle and take your measurements at the wall mark and the template and do the math.
Make sure to measure on a vertical line and to the same location/corner of your template to allow for the dihedral tilting your template. The clamp should be weak enough so it doesn't collapse the tube completely. A couple of finish nails spaced correctly would work as well. Your template could be as simple as a 5' 2x4 screwed to a 6" 2x4 forming an L. The small leg points down and aligns with the rear edge of the wing right in front of the aileron. Measure to the top of the 5' 2x4 in all locations. Have fun!