Can you please post the photos so we dont have to down load to a file to view.
No, the dimmer coil resister unit is completely different nore part of the horn switch. It looks to be Model T era. While the early Fordson tractor used the same switch as the car, they may have used a more permanent key that wouldn't have fallen out bouncing across the field as the coil box was out in the open.Headlight resister????