I don't totally understand what your test pictures are showing, and would *highly* recommend using a good focus test chart like the one at
Home when doing this sort of thing. It's designed to work well for AF, but also works fine for MF.
EDIT: I finally figured out your picture - we're looking straight down, and one label is closer to us than the other (raised off the floor, presumably). Clever. But you're still much better off with a good focus test chart.
Anyhow, doesn't the Katz Eye come with shims to use to adjust the position of the screen? Many third-party screens do. I think you need to get it further from the mirror. If there is a shim between the screen and prism, remove it.
Also, I've heard it claimed the Katz Eye screen don't suffer the following problem, but it is worth checking: most stock focusing screens show entirely too much DOF at large apertures. With my A50/1.7 wide open at f/1.7, the screen might show 20 lines of text in focus when looking at a newspaper at an angle, but the picture itself will show only 0 lines in focus. Not until I stop down to about f/3.5 does the focus screen show what the picture will show. Until that point, the DOF preview is useless - it doesn't show any aperture changes at all. So you have to accept that something might be in focus in the viewfinder but not in the picture, and learn how to anticipate this effect and not just make sure your subejct is in focus, but in the right position (toward the front, or toward the back, depending on how your screen is adjusted) of the focus zone.
Again, supposedly the Katz Eye doens't suffer that, but it's certainly worth a test.