Thanks for the link to the manual. I am learning the parts to my patcher are unique or better yet obsolete unless I can find another 29K51. My needle plate release lever pin is worn away and I am considering fabricating a new one to replace the old one. Can the gear box be changed to use another from another 29k with the same size arm if the pinion gears become worn and need replaced? I machine works well as is and I wanted to know how to remove the box so I can clean and lube the area.