I got the trunnion cylinder machined to size and hand fit to the base. It turns nicely with no slop. This ended up being way more complicated than I thought.
Now some sketchy work holding for the milling operations:
View attachment 491565
It should be OK since the jaws are 1.5" high and the cylinder is 3.000"
Order of ops?
My plan is to cut the flats where the spindle hole is, and then drill the spindle hole out to 1", then bore to final ID of 1.688.
Somehow I need to remove this to press in the bushings and then get it perfectly re-indexed to bore the bushings to 1.500. Formidable at best.
Then I need to rotate 90 deg and remove a metric **** ton of material.
This is the component I have been dreading.
You got a better idea?