I acquired a Mars Mercury lathe several years ago and have only used it for turning. Thought I should get the screw cutting feature working, but firstly am not sure what a full gear set consists of. Two available gears have stripped teeth - one which is attached to the main spindle, the other which has an extension on which another gear mounts. Both stripped gears should have 30 teeth. The two joined gears shown in the photograph mount on the bare shaft shown in the photo of the gear train.
Questions are:

Are any operating instructions available for this or other Mars lathes?

What constitutes a full set of screw cutting gears and are these still available from any source?

Any information would be greatly appreciated. Photos of existing gear arrangement, damaged gears and name plate attached,
bobmac