So i've researched the forums looking for a definitive answer on shims in the differentials. From what i've found, people add shims to reduce the "clicking" noises or eliminate the occasional "rough" hang-up or catch between the ring gear and differential pinion gear; which, is what my basic issue is. I also read that 6mm shims are the recommended size and usually 1 or 2 are needed.
I just rebuilt my diffs, and still have the profound clicking noise, as well as a slight snag at one point between the gears, which occurrs in only that one spot. Further inspection of each tooth on both gears reveals nothing which would warrant replacement - Everything is a brand new piece...!
Lastly, I also noticed that when rebuilding the differential housing with the bulkhead and shock towers, if i tightened the screws down, the outdrives from the diff would be almost impossible to turn. I had to back the screws out a couple turns to allow the outdrives/diff, etc. to spin. Why is this the case? I would imagine that not having tightened down screws could lead to a possibly weaker structure; or, could back out through repeated use
I will try to add a shim or two to hopefuly solve my issues.