Well it good to see you got the pictures posted. Larry had been talking to me though pm's about this and told him to post the pic's, when it came up the tractor is a Wizard branded one.
Some history first. This tractor was built by Edko in Des Monies Iowa from 74 thur early 78, when the company was bought out by Areins, who took one of the 3 models and sold it under their own brand name. Edko was the orginal builder of the Plow-Hoss one wheeler, (which is still being built in MS, someplace), The Walking Tractor, which is the two wheeled one in Larry's pictures,. The last model was a tiller machine was built that could be converted to a 2 wheel tractor also, but i cant recall the name right now. Wizard was the brand name of Western Auto for who Edko built Larry's machine. Some place in this site are pictures of my Edko Walking Tractor, with its 5hp 6to1 gear drive. The patented part of this tractor is the reversable, adjustable hubs. the tractor goes into reverse by moving the clutch lever the oppasite direction from forward travel. I'm missing the R parts from my tractor, but basically you just have an A belt that runs between two pulleys and as you move the lever forwards it causes the rubber pully to rub the outside of a pully. As you slack one belt the other one turns the other pully group The 5/8 belt is the main drive one for going forwards. Looks like the pullys is on the shaft backwards in the pictures. See clear as mud,,,right. Trust me this type of reverser has been used since at least the thirty's. All my big Handiman units use it.
Since you have all the parts short the belt it should be easy to get a measurement of the one missing. I havent played with mine for a while, as the last time i looked, one of the patented spring inside the hubs was broken, so mine only drives good one side. the adjustable part is simply a C clip, on the axils, that let you widen the wheels or narrow them up, with out having to change any linkages. Most reversing hubs have some fixed point mounted to the tractor frame that cause the motion to flop from forwards to back, this tractor has it built inside the hub completely.
I have tried before to get some answers about the company without having to drive over to Des Monies, but i think maybe there was some hard feelings involved in the breakup and no one wants to talk about it. I did see at one time the Trade Marks for the Walking Tractor and the tiller unit were for sale.
Good to see something new pop up, as there cant be many of them built and probally fewer left running. I also called these the last of the line, as far as walk-behind tractor went. Most other lines got out in the 60's, but these guys started one up in the late 70's. I also find it interesting that most of the ones i know about are down south.