Farmall Tractors

Any advice on the easiest way to go about doing this setup? It looks fairly simple, do I put the hose straight or in a circle and how does the tractor sprinkler know to stop and come back?

There should be a little ramp with the sprinkler. Arrange the hose in the pattern you want the sprinkler to travel, being careful to not make any curves too tight. Set the ramp where you want the sprinkler to stop. When it hits the ramp and climbs it, it stops. Hope this helps.

and farm tractors to use, it must also be suitable for pedestrians what would your suggested surface be? Please note tarmac would be unsuitable in summer for horses and concrete to ugly.thanks for any suggestions

Would this be any good to you?
Not seen it in use but seen it (or something similar) demonstrated at various landscaping exhibitions.
http://e3innovate.com/homeAndStabiliGrid.php

D series was in the 50's, I remember in 1957 they offered power steering on the D-14, but I don't remember the start and stop years for the model.

Try this site. They're really 'into' vintage tractors and someone will be able to help you.