Help with a MSphysics script, please?

[pacaeiro]

Good night to all. This is my first post, and I thank you in advance for reading it.
I'm very new in MSphysics and even more in Ruby script, that's why I'm asking for help.

I've made 2 simple gears, one with a motor and the other with an hinge.

My problem is:
I want to make a simple counter linked to each gear (maybe a label text) that shows the number of turns each gear spins, to see the gear ratio that I'm obtaining, if it work with compound gears to, it will be amazing.

Can you give me any clues about how to do it?

Thank you very much!