You have it.

In Carol's pictures you can see that she set zero at 90 degrees from the tube, but it really doesn't matter that the scale match the actual azimuth direction, only that the scale and pointer indicate properly. Her approach makes it convenient to see when at the eyepiece when the scope is pointed north.

Using the approach where the scale is attached to the rocker means that you will have to leave the eyepiece position at times to line up the pointer. The approach I used is to put the scale on the groundboard and build some adjustability into the scale rather than the pointer. That allows the pointer, attached to the rocker, to be visible from the eyepiece at all times, a little handier set up, but a little more complicated build.

Let me know if you have other questions.

Clear Skies