Ring Gear Contact Pattern

I'm not an expert but I have done a few setups and will try to help. From your description it sounds like you have too much pinion shim. Have you tried no shim at all to see what pattern you get?

http://www.mopar1.us/backlash.html (note chart is at the very bottom of the page)

Here's another page on setting up gears

http://www.mopar1.us/setuprear.html

And here's yet another page. This one has a ton of info.

http://www.pirate4x4.com/tech/billavista/Gear_Setup/

Good luck