rear axle adjustment opinions

[Nacho-RT74]

in the hunt for the cause of the "turbine" or "ghost" noise I dissasembled my 3rd member and search for the pattern I was getting... got something similar to 1st attachment.

Specs are:
Yukon SG, street ( smooth ) version
NOS 3:55 gear set
489 housing
New bearings all around
New collapsible spacer
0.032 shim

Then make some adjustments, changing the shim for a 0.025 one to get far away the pinion from the gear and print the new pattern. get one similar to the second attachment but pattern on drive side wasn't that rounded, more triangle like the blue mark. Made to reduces a little bit the noise but is still present, specially when release gas pedal. I can say maybe I reduced the noise when gas pedal is pressed in around 40-50% and when releasing gas pedal in just 20-30%. Do you remmeber the vibrations I was getting ( exposed on another thread ) ? well made to "jump" the vibration from starting at 70 MPH to maybe 80 MPH... and is less heavy, but still lot noticeable. Is like some pulsating vibrations. I still have to check tires/rims balancing anyway though!

I DON'T HAVE THE TOOLS to check backlash but I can say I left and feel a slight play on pinion ( holding the carrier ). Maybe I can move the yoke about 1 milimeter.

Emailed to doctor diff and he told me could it be pinion is still too close &/or backlash is still too tight

Next shim I have is 0.022 dunno if that will be an enough step if that's the cause and watching the pattern I got. But REALLY is the backlash TIGHT If I can feel a play like stated ? I was thinking in fact the cause could it be backlash loosen!

[Nacho-RT74]

Beside that I can feel quite often also a slight clunk noise when releasing suddenly gas pedal.

crossjoints are new too!... Well one of them is fairly new the other one completely new.