I'm working on some steam-punk/mechanical world style virtual table top maps that have a lot of moving terrain in the form of giant cogs. I would like to help folks visualize and track the movement, and was wondering what others thought would be the best aid in that regards. Is simple arrows to track the direction of movement of each cog and instructing folks to just move any characters on a cog one tooth over enough, Should I include a bar whose center of rotation can be easily matched to the cogs to measure rotation, or should I include multiple templates (which gets complex as each number of teeth would need a different template)?

Here's a small version of one of the maps so you can get some visuals:
Clogging my Mental Cogs: Best aid to track movement-mechancial-help.jpg