I finally made a fairly accurate circular "dial" that I divided into 32 sections to use as scale to use with the arm adjustment knob I described earlier. I had been using a piece of tape I had marked and divided freehand, by eye. I had already determined record thicknesses that correspond to points 180 degrees apart on the dial's compass. From this point it was easy to assign a relative record thickness to each of the 32 "spokes" dividing the 360 degree dial. I actually drew my scale as two concentric circles. I pasted the smaller, inner circle on the arm under the adjustment knob This smaller circle is too small to write legible numbers on, so I wrote the derived record thickness numbers on their corresponding "spokes" on the larger, outer circle, which I use for a reference/guide for settings.
As it happens, I have only actually used about 240 degrees of adjustment, from the thinnest to the thickest records I have played since i started this system.
As it also happens, successive marks on the "spoked" scale correspond to .0031" incremental differences in record thickness with this WTR arm, and this has so far gotten me close enough in terms of relative/correct VTA, once I know the record's thickness.
It does not take long to measure a record for thickness and label it. Once that is done, it's done and I can listen lots more, and I can listen to records with less trouble in hot weather now. I very seldom get up to re-set, once I set and start and a measured LP. Basically, it's all good, a very relaxing way to go.
I can't think of any way to improve this system, so from here it's down to observations about the sound of various labels, recordings, curves, etc., and these will appear elsewhere.