Carol,

When you get tired of hearing from me, just say so.

With regards to aligning the base, I have a cheap $4 compass permanently installed in the base of my scope that helps me get somewhat close to north when I set up the scope.

Then, to "calibrate" I use any known object, many times a star or planet visible well before Polaris is visible. Center that object in the field and adjust the dial to match. My approach was to build it about 20 degrees of adjustability on the dial. That approach allows you to adjust without disturbing the position of the scope, nice if you have spent any time carefully leveling the base.

Remember that each time you move the scope base to adjust your calibration, you will likely move the scope enough to loose the calibration object and will have to reacquire the target and check the reading and repeat. Might be a bit tedious.

An approach I have seen in a set up like yours with a non-adustable scale is to make the pointer movable. One way to do that is a pointer mounted on a magnet that attaches to a steel plate along the edge of the scale. Once centered on an object, You simply move the pointer to match the appropriate reading, again leaving your scope undisturbed, still level and centered on your calibration target.

Hope this helps.

Rod