Optimal parameter settings for most accurate stationary/slow orientation? (Trying guide telescope using imu/gps)

I have a spare pixhawk and m8n gps I want to use to auto guide a telescope (roughly). This is just for fun and I’m not expecting it to be very precise. Basically I will zero the orientation pointing at Polaris, then use the gps data and starchart data to be able to guide the telescope to whichever object I want to see. What are the best ardupilot parameters to optimize my orientation measurements? Is it possible to set accel/gyro sensitivities to their lowest values (2g)? Use ekf1/2/3? Set it to fuse imu data? Or just grab raw imu data and calculate orientation some other way? Any input would be appreciated!

That’s great. I also have 2 hobbies, model airplanes and astronomy. And I was thinking in the same direction. But I have no clue as I’m a software nitwit. Hope you succeed in your quest.