Hello all,
I removed the fixed jaw, cleaned it (there was a fair amount of gunk but not much in the way of debris), and slid it under a plunge indicator. There might be an argument for 0.0001 in variation, but not much more than that.
After careful cleaning and replacement of both jaws, I indicated the vise on a clamped parallel as I have been doing, and had a much easier time than before. The end result is essentially what I saw on the "part that ate the tap", only w/o the bounce from the finish.
Just as with the bolts on my mill's column, the jaws must have been attached by King Rong ;) I finally ended up standing on the Allen wrench to loosen the bolts; with my hands, I was afraid it would break loose and a finger would follow - they were that tight. I put them back with a fairly good tug on the same wrench, but not nearly as tight as delivered.
Bill