but I want to say that my gut feeling is that it shouldn't be done by pushing on the blade tips, rather as close as possible to the center of rotation (shaft).
You can go ahead and say that if it makes you feel better, but your belief will not be based on any fact of engineering as there is absolutely no difference in terms of impact whether you use the hub of the tail rotor or the outer portions of the blade.
What you will find with the entire Huey series is that when manipulating the tail rotor by hand there is initially some slack before the drive-train begins to rotate. First take-up this slack and then rotate the tail rotor using smooth/even pressure (not jerking it) and rotate the blades to the desired position.