Beware ~ Aluminum degree shims will crack and "spit" out in time. WFO sells steel ones, DIY may have them too.
I had one fail on me years back. I did not see that I lost the shim during a wheeling trip and my ubolts were loose because of the shim being gone. My spring perches were rounded/bent destroyed. Had to cut them off and replace. But that alowed me to clock my pinion up and remove the need for shims..
Just my .02c from the past
Keep those Ubolts tight!
Burt