I Just got an American Scale Co. #78 vise. (why they made vises, I dunno!)
It weighs 150 pounds, has 6" wide jaws, and . . . wait for it! . . . has a swiveling rear jaw!
I have seen these around for decades, have wanted one since I was nursing and in a crib, but never found one at a price I could stomach.
Well, I just did and I am BLOWN AWAY!!
Check out this little video I made to show the advantage of The Swiveling Jaw: