If your gears are stripped, you can reuse your motor and just replace the shaft and gears with this steel kit.  This kit uses a small factory style worm gear and a metal large gear mounted on a custom machined shaft.
 
You will need to use the provided front thrust washers and your factory rear thrust washer. The small thrust washer on the small worm gear must also be reused along with your factory tube nut.
 
If you want a small metal worm gear, see the other product. Two metal gears meshing together cause a noticeable gear whine.  Watch both videos to hear the difference between a factory style worm gear and the metal one.
 
This kit has a lifetime warranty covering any gear breakage.
 
Don't forget to buyTribolith Grease !