Turns out the runout was easy to fix in this case.
I bit the bullet and removed the chuck to see if it was systemic or just the chuck.
When I measured the spindle runout, it was nominally zero where the spindle was clean. A previous owner appears to have had chuck fallout problems and "fixed" it with epoxy. After cleaning up the spindle and the chuck taper, it is now less than 3 mils, down from about 12 but the chuck would not stay but a few drops of super glue fixed that. Apparently CA did not exist back then and epoxy was the fix at the time.
I also have learned that there are not only different brands but serious design differences in the rebranded versions. I found 3 different manuals and only one agreed with mine in a very serious way.
Turns out mine (PowerKing logo) has one continuous oilite type bushing the entire length (6") of the quill. The others and all other drill presses I have seen, have small bearings or bushings at the top and bottom of the quill.
I think this pretty much deals with the issues of side thrust when used as a mill. You couldn't ask for a bearing more suited to side thrust than this.
I have another thread going on this topic...
https://www.hobby-machinist.com/threads/pulley-ratios-vs-the-real-world.78380/
Here is a pic of the current configuration with the new XY table and the home brew trans feed that is still a work in progress but working.
View attachment 305894
