Your '51 looks a lot like my '49, condition wise.
I just completed my spring plowing with it on Saturday. When I had to drain the calcium
ballast out of a rusted out original rear rim a couple years ago, I was worried how that would affect its plowing ability.
Oddly enough, it made it much better, and saved me a considerable amount of gas, compared to what I used when both rears were loaded. The loaded side is the sod side, which typically has poorer traction, and sees less “down pressure” from the plow.
Eliminating the added weight on the furrow side rear, evens things out, allowing the plow to pull more evenly with significantly less tractor weight. Less tractor weight means less fuel usage, so long is there is no wheel slippage. I plowed an extra acre or so, with the money I saved on fuel.
While the 8n does plow better now than it did when it was delivered to my neighbor, from the dealer in 1951, the same can’t be said about the two row cultivator. It’s bad on that tractor now, with lots of wheel spin on the unloaded side.
Because of that, I now cultivate corn with my much newer, 4wd loader tractor. That has both rears loaded, so it pulls the cultivator very evenly. I also mount a sprayer boom on the loader arms, with nozzles lined up with the rows, so that I can spray the rows with gly, as I am cultivating.