[Azimov]

This is pretty cool and I'm glad you bumped it. I have my own ideas tumbling around in my head ATM and find this inspiring. The use of the pen car circuit is pure genious. I could kick myself for destroying mine over a year ago for parts.
I'm no gear ratio expert, but from what I can gather from your text, your final configuration is 69:1. That's a good healthy bit of torque there. If it's lifting the weight you're looking for in a reasonable amount of time, then I'd say you've got it licked.
I know you want an accurate number so you aren't making any missteps in your future tutorial, and honestly, I'd like chilli or someone to confirm your findings so that a range can be found that will easily lift an MT without taking an hour to do it.
But, from what I get from your project at this point, 70:1 is a good scale ratio. I'd say anything between 60-100:1 should work very well.
EDIT: A motorworks motor should switch out with that pen car motor. It has the three wire connection as well.