Just finish the tractor with a trailer and here's a few pics of how I made the wheels. I drill the inset first then use that hole to center the hole cutter, cut half way turn it over and cut all the way through. Then I have a nut and bolt to fit the hole put two nuts on and then push that into my lathe right up flat to chuck which keeps it flat and round, then turn sand and wax job done as they say. Roly