An odometer, 60kph speedometer, and an hour meter that has minutes on it? Interesting!
They had one at the Porsche museum in Stuttgart 15 years ago when I visited. I didn't have my tractor then so I didn't give it a really close examination, especially with the other hardware in building.
I guess building a tractor is a good way to get into making complicated things with motors though.
The US is actually the oddball in the world in that the automakers and ag equipment makers hardly overlap at all. Ford/New Holland obviously being the big exception until Ford sold everything off and only the New Holland name survived.
About the only other overlap I can think of is a few ag equipment companies using things like Chrysler industrial engines and Chevrolet/GMC industrial engines for powerplants, mostly before diesel became dominant in the 60s.