Having spent the early part of my life using wood blocks and sledge hammers to get properly preloaded carriers into place (final stack + 0.015" per Dana requirements), I decided when I bought my e-lockers years ago that I wanted to do it "by the book".
I got my spreader off eBay - similar to this one:
https://www.ebay.com/itm/2539677991...d=link&campid=5337789113&toolid=20001&mkevt=1
It works fantastic and makes setting carriers in place remarkably easier and as
@NashvilleTJ pointed out, it's pivotal for proper ARB installation.
A photo of the one I actually bought (but eBay tells me he is no longer an active seller)...
View attachment 270372