Replacement of plastic gears

Are there instructions someplace that describe the process of replacing the gears?

I have to replace the gears on one of the servos because the top gear on the motor shaft has broken teeth on the top. When putting the new gears on, the top gear on the non-motor shaft has two plastic stops on the bottom. I assume that I need to zero the servo before placing this gear so that the two stops protruding from the bottom are centered.

What kind of grease do I need to use on the gears?

Thanks

Chuck

We have instructions up here:
makezine.com/projects/replacing-9g-servo-gears/

Not sure what grease these come with, but it looks like lithium grease?