Step 5: Add a Hardy
SInce you can't drill a square hole through steel, I made my hardy hole round. (5/8") I then tightened a bolt and nut through the overhang, bolt on top, and welded the nut in place on the underside.
I made a number of hardy tools, welding them to the head of different bolts and oriented across the anvil face. They are nothing like as quick to use as a hardy, which can be removed and replaced in a second, but they do the job.