So, I'm not sure this would work well for what I'm looking at, but here is how to get a square hole. Just would have a hell of a time getting it back out of round stock. Ha Plus, this guys channel is just hilarious.
I like the idea of the pritchel 'stand' myself. Was thinking of doing that myself, as I do not have a traitional anvil. Just a big block of steel. Now, how to fit a square peg in a round hole and make this a Hardy tool holder.