I wasn't able to figure that one out exactly, due to the way they logged tractors on the summary sheets during 1964 and 1965. I was able to find 418 agricultural Oliver 1850s with front wheel assist from 1966 on through the end. If was to guess on the other two years, I would say the grand total was near 600. This doesn't include Cockshutt or Industrial versions.

There should be more accurate numbers later this year, as the build cards have been read and put into a computer database. They've got some work to finish it up, but that database will tell exactly how many left the factory with what.