Mechanical advantage....and the Fridge Truck

Recall we had explored an option to LIFT the fridge truck with our motor.  In short, the cool magnet holder had promise but the motor did not have the torque needed to lift this heavy table element.  We opted to not explore gears given time constraint.

Well, Brain Davis had some simple gears that were of interest and might be usable without too much modification of our existing attachments.  We gave one a try and with a battery at 6.7 we accomplished the following lift.  It still needs some exploration.

Two useful resources for gears.
Worm gear casings
Tutorial on gears.....the above video uses a 12 driving a 20...what is the mechanical advantage???  (more than 1, less than 2)  How can we get more?