8 3/4 gear set up help

That is what I was thinking.Actually, the original shim puts the pinion in the exact correct spot 2.767.......go figure.
Last round with it out, I did go negative .007 and it went nuts, so I went back to .042 and went up and down from there.
I am beginning to think I got a bad set of gears, but not ready to say that yet. It seems unlikely.