Captainlip.
I have read through the entire thread and there has got to be an obvious problem with your gearboxes if you are going through gear at the rate you suggest.
If you input shaft is moving around so much, it maybe worth checking that your bearings on the input shaft haven't collapsed, which could be causing the excessive movement. There is certainly no need to put extra shims in here, it simply won't help. If you are putting extra shims in you are using them to cover up a problem which lies elsewhere.
As of yet we are still to hear from you directly at Team Durango, as other people have mentioned on this thread, it's how we deal with our customer service questions, we don't deal with them on forums as it prevents us from dealing with any issues on a one to one basis.
The diffs were extensively tested and have been run by the team for nearly 2 years now without any major issues. There are no other parts being used by the team, everyone has the same parts that you do and the build guide on the TD website:
http://www.team-durango.com/blog/?p=2584
Was put there to answer the most commonly asked question we had as to the proper methodology in building our diffs.
Most cases can simply be rectified without the purchase of any new parts, there is usually a glaring problem which is found and resolved quickly.
Could I please ask you to contact
[email protected] so we can help you to resolve your issue.