Made some more progress today...

The motor didn't have a thrust washer for the primary gear when I stripped it down, so with some trial and error I finally was able to get my end float down to .006  I realize that 6 thou is a little on the high side, but I tried a .112 thrust washer and had .012 float, and the thickest washer I could find was .118, so I'll make due with what I have.