There is a lot in what LeFusil said. I used to fool with the antique two Cylinder John Deere's a bit. You should see some of the Fixes that have been applied to them. Most of them worked, but were anything but Original.

Collectors today complain ferociously about these "Fixes" but they kept a lot of tractors in the field & producing for their owners.

Miller/TN
I Didn't Say Everything I Said, Yogi Berra