Far from being perfect circles yes you are right.. It's like a pair of mobius with broken links to the loop or chain.
The engines are mirrored the same the other side. The spindles when closed at the top point north, east and west and the spindles at the bottom point south, east and west.
Just so you can see it more clearly sorry about that, I honestly never knew that. My Bad!!!
They are perfect circles in Star Wars though...