I think the best simplest solution is to utilize a simple RTC/Calendar to drive a stepper motor gear drive at a constant sidereal rate for a single axis right ascension movement.
If you research telescope clock drives using polar mounts you will see that it's pretty simple, accurate and reliable. You may need to manual adjust the azimuth angle manually every month or so to optimize performance. The RTC/Calendar could also handle the skewing command to reposition to each sunrise from look up table in your program.