Took a lot of work and fiddling, but here we are! The big thing I learned is why my grandfather had one of his rear wheels set to wide stance and one set to narrow on Bror. It was because if you have it on the narrow stance, you can’t fit the rototiller onto the back of the machine.
Also learned how to get the fluid-filled tires onto the hubs. Set up a piece of thin board onto a wooden dowling to use as a ramp, then roll the tire up until its in the right spot.