The main pair of scissoring arms are what will control the calendar part of the mechanism. The short rack of gear teeth will mesh with a set of gears for a drag-fan that will spin and soften the motion of the arm when it drops at the end of every day. Kind of a fun part to make.
The smaller lever (lower right of the first pic) will move the hand for the day of the week.
It will all make sense soon, I promise.
