Harry K wrote:
....

Different type of 'plow bolt' than I was familiar with. The ones I
knew bolted the plow share on. they had a flush, flat head just as
the elevator - had to be flush to keep the dirt from catching. Of
course I was wrong in that the 'plow bolt' did not have the square
under the head, they only had one 'tit' to keep them from turning.

Right on...

Most plow bolts do have square corners -- essentially a flat-headed
carriage bolt. The one-sided version are a variation.

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