Sorry it has taken so long to answer. I take it this is your first time setting up gears. Keep at it and don't give up and you will learn alot.
I have only setup to sets of gears an AMC 20 and a Dana 44. The dana 44 I did is very simmilar as far as gear setups go to CJ dana 30's. Here are some of the things I learned, that may help you.
1. VERY Importent. Some Dana's used Oil slingers and or baffles on the inner pinion bearing. If the axle housing in question used them then they should be reused. If the axle housing did not originally use them then they should not be used. If you try to use a slinger and or baffle in a housing not originally using them you will not be able to get the pinion far enough away from the ring gear
. This could be part of your problem.
2. Your idea to measure the depth of the pinion bore in the housing and calculating to get a starting pinion shim is a good idea. I did this on my second axle setup and it made things way easier. There are however some details that are importent to remember.
The depth marked on is either an add or subtract from the standard depth, or the depth measured in line with the pinion to the center line of the housing (square to the pinion bearing race seat) see the distance marked "checking distance" in these links Free Automotive Differential Ring and Pinion Gear Installation Instructions
. From your discription I think you measured correctly but It can't hurt ot be sure.
Your starting shim of 0.075" sounds very high, usually the pinion shim is closer to 0.035" on Dana's. It could be that your tool is not mearsuring in the corect dirrection which could lead to overly long readings. I would like to see a picture or discription of the you used, the method I used was very crud and involved a magnetic stand and dial gage and a lot of screwing around.
3. This makes no sence to me "... the track was tward the pinion carrier i moved the pinion out ....". If you could dicribe the pattern using the terms (root, top Land or tip, heel, toe, Drive and Coast) deffined in the links above it would greatly help me and others help you as they are standard terms. Pictures of the Pattern are also a big help.
Moving the contact pattern in the Heel to Toe dirrection is done by changing backlash. Moving in the Root to Top dirrection is done by changing pinion depth. This may seem kind of backwards but it is correct.
4. When making a pattern turn the pinion in both directions, while putting drag on the ring gear this will make a clearer pattern to read. This will also remove any slop in the location of the gears.