Well, I believe I can now put this issue to rest. I happened to actually read the accompanying owners manual that came with the cutter this morning (imagine that!). It plainly says on page 25-2 in an important note: Recommended hitch pin size is 28mm (1 1/8 inches) diameter and at least 7 inches between the pin shoulder and the spring locking pin hole.
So, they delivered the tractor and the cutter with the incorrect pin size and told me it was the correct pin! I will be contacting them this morning. They owe me the correct pin.
So, they delivered the tractor and the cutter with the incorrect pin size and told me it was the correct pin! I will be contacting them this morning. They owe me the correct pin.