Last year I wrote that I finally sold our old 8-N Ford tractor and got a new-to-me Ford 2000 that's only 40 years old. So far, so good on that - it's ugly (minor body blemishes) but it runs great. It has more power than I'll ever need and several gears that will probably never be used.
The only issue I've found is that if the tractor is cold and/or wet it is hard to start. The reason is that Diesel engines run without spark plugs - just the compression of the fuel/air mixture generates enough heat to cause combustion. Unlike many newer tractors and Diesel trucks, the old tractor does not have glow plugs to help and must depend on compression alone to get the fuel mixture to the ignition point - a lot to ask from a 40 year old engine.
The solution is ether, which has a much lower ignition point than Number 2 Diesel. I saw several figures listed on line, but the ignition point of Diesel as about 500° and diethyl ether (the main ingredient in starter fluid) is a couple hundred degrees cooler. That's a quick simplification of several hours of reading about how diesel engines work - flash points vs. ignition points, etc. The bottom line is that one quick spritz of starter fluid into the air intake, and the old girl fires right up.