At the risk of asking a dumb question, how does that boring bar mount?
Looks like a standard clapper box accepting a lantern-style toolpost. Usually there's the moral equivalent of a two plates sandwiching the hole with a threaded rod to keep it all together, but this one looks like it's just kind of setting there. Maybe the clapper is locked and the bar is threaded to a plate inside the clapper?
Very nice machine - im sure the Clapper box adjuster top arc bolt washer n nut need help. Thick hardened washer would have stopped the tapered wear in the arc. But she is still a great shaper few upgrades repairs and splines keyways and machining will be going on with her prioritisation. I like her