G'day Mo,
I would start at 110mm from leading edge, it should hange so the the tailplane is level, or as you would call it, the horizontal stabilizer.
Make sure you use the recommended elevator throws, on low rate, & set high rate to 30% more, in case you need the extra control, I do the same for the ailerons, the rudder throw should be low enough throw to allow taxiing, but not too much to cause ground looping, Cubs are notorious for that, always & I mean ALWAYS, hold full UP elevator, until the plane is moving then release, & add power slowly & SMOOTHLY, when taking off, & steer with rudder.