Thing I find most amazing about those years, say 1965 to '70 was how many trips over the fields they made spreading fertilizer & spraying for weeds or bugs.
Good thing fuel & labor was cheap! I'm also surprised more of those tractors didn't have duals, only the 5020 and new 1256/1456 FARMALL had duals. I can understand the tractors working hilled or bedded ground not having duals but in my opinion anything on flat ground should have had duals. Dad got his first set of duals about 1960, and was using duals on his FARMALL M to plant with by 1965. ANY tractor that did fieldwork had duals or a different tractor with duals did the work.