Had just a few hours to play a little bit more with polar alignment and take a test shot.  This is a stack of 5 2-min non-guided shots and 1-dark shot.  A few lessons to try for next time: (1) somehow put a piece of foam between the lens and the scope to keep the lens from shaking, (2) use RAW format, (3) remove front UV lens (I think this is creating inner reflections), and (4) take pictures on a clearer night!  Also might help to stop down the lens one or two stops.