As noted before we needed to adjust the Jig for positioning the rear columns (as this had arrived with the castings) – so a nice first job to skim the requisite 62thou skimmed off the head of the jig..
A flycutter on the Vertical Mill soon achieved the desired result – I would have prefered to do it on the shaper (no risk of dishing, but it was too big for the table.
This jig corrects the location of the rear columns as it is located on the face of the main bearing housing which was machined too wide on the base plate. The picture here shows it in position temporarily supporting the rear columns (one with the slideways faced…)