Farmall Cub

There are a pair of "snow plow spacers' on ebay; #4304679979.
What are they for? Where do they go? Should I have a set of these for my plow? Inquiring minds........

Marion, those are the blocks that go into the square openings on the front casting of the tractor. They have a 5/8" hole drilled through them for the long bolt / rod that attaches the brackets to go through.