Modern tractors already drive themselves. Every brand, from John Deer to Fendt and CNH sell tractors with AutoSteer. Every farmer will get a set of GPS coordinates for their fields and the tractor will then drive without human input. The only thing nowadays what a farmer does in a tractor is lifting or putting down the machinery they tow. You don't have to accelerate, brake or turn the tractor. It's all automated.

https://www.youtube.com/watch?v=AHVr3wderFg

And the step I'm working on is to remove the driver completely. And I don't have to worry about road signs, streets, traffic and similar stuff. Far easier and it will be there sooner than you think.