Best place to mount a vise?

image.jpeg image.jpeg If mounting in truck receiver hitch weld a nut flush into both sides of hitch part. Then you can install a bolt into both sides and tighten to remove any play.
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I have also welded a receiver tube vertically into the top of my heavy but mobile steel welding table . It is also tightened with a bolt to keep it from wiggling. On the other end I mounted in similar fashion a bar to support longer heavy items once in the vise. Both are removable and adjustable for height.