How much play is acceptable between the quill and the main casting? I'm measuring .0045" front to back and .0035" side to side/
That seems like a lot, but I've never measured. How are you measuring?
11/22/2024
I saw this photo in an estate sale ad. I saw that the left guard was broken off and went to check it out. It's a great parts machine if the price is right.

It was marked $30, but was day 2 of the sale and I snagged it for $20. This is a model 115.7575 (#4). I did find the broken left-side guard with a good left cover and discovered that the Vimco lamp shade was fubar.
I walked around some more and found the grinder pedestal stand. Ah... it's a no-brainer that the grinder broke when it fell over on the stand. It was very obvious that it was a long time since the grinder was on that stand. The stand came home with me too.
This will likely be a parts machine soon.
More pics after I got them home. It runs good and the rotor/arbor shaft is straight.

11/23/2024
I bought another 115.7575 (#5) today. This one has a couple issues, but with parts from yesterday's buy, I'll have a very nice refurb.
Removing grinder flange nuts
By far, the easiest, cheapest and safest way to remove grinder flange nuts is to use a jam nut on the right side.
- use a wrench on each arbor nut
- remove the right side nut first
- remove the outer flange and stone
- thread the jam nut and the original nut back onto the right side arbor and tighten them against each other
- use wrenches on the right side outer jam nut and on the left side nut
- remove the left side nut
- remove the left outer flange and stone
- loosen and remove the jam nuts from the right side arbor