The pinion needs to be a little closer to the ring gear. Since you have gone -.002" from the original, another .001" or so should get you where you need to be. No exact formula at this point, let the pattern be your guide. Normally you wouldn't need to go this far from the original shim thickness. I'm thinking your are using aftermarket gears, they don't seem to follow the guidelines I mentioned earlier regarding being able to use the same shim. This is not an issue, just takes a little more finessing is all. I believe you mentioned the pinion was marked with a +1, as you can see, you will be farther from this when you are done. Another possibility is that the gears aren't original, and the shim was changed in the past.

Happy New Year.