Old Mart,

I have a favourite way of tramming vertical mills which allows you to keep the spindle vertical while you tighten the clamps. You might like to try it.

Mount a lathe faceplate on an adaptor which allows you to locate the combination into the Morse taper socket. Wind the quill down so that the plate makes contact with the table and with the clamps just gripping, apply pressure to the quill and nudge the head about until full face contact is made to the table. Keep the pressure on and tighten the clamps. Bingo

Regards Brian

See my comments in This Thread about the tool I built, and also the link in my post to the one built by John Moore, Bogstandard, from where I drew the inspiration for my design.

For the one I made, I used an MT2 arbor, as that will fit both my mills directly, as well as the bench drill.
Note that the important part, is that the two feet are in a plane exactly perpendicular to the axis of the arbor, which I achieved by lightly skimming them with the arbor held in the Myford's spindle; The size of the gap bed was the limiting factor for the beam length.
The device then becomes self calibrating, by just standing it on a flat surface.

Seen here in use, the mill is about 18 thou out over the length of the gizmo

Alternative setup with the table/head now trammed

Bill

I appreciate the problem as the Dore Westbury can be a bit of a pain, though the bolts are in a different place.
The reason I posted the photos of the tramming device, is that you can see what moves as you tighten things up.
Hence if you notice it always kicks, say 5 thou anticlockwise, you can set it up the same amount clockwise, and it might even out to zero as you nip up the bolts.

Bill