I grew up running a 1952 Oliver 77 for a farmhand feed tractor and a 1962 Oliver 770. They are both still in use today at my parents ranch. As it has been mentioned, they were way ahead of their time.
I think the thing that impressed me most about the pair of them is the 77 will start if you can get the motor to spin. I swear I have seen that thing with a low battery spin about 4 RPM and still fire up after about 1 revolution, and this was was in a cold South Dakota winter.
If you need any information on them let me know.