No forging, just learning to weld and had some free junk from work. The shank is improvised square tubing from angle iron. Couldn't fit as I went as the welder is far from the anvil. I did have some measurements but the hardy hole has some wear so the narrowest point is narrower than I was able to measure. Probably just use an angle grinder. It's close and if it breaks, I'm out but a little time and up quite a bit of experience. Order of operations is certainly an acquired skill.