There is no need to change the pinion gear position, which makes this install less painful. However the differential change still requires the setup of the ring gear relative to already installed pinion gear, which means that you have to set the backlash and check the tooth marks.

The biggest problem I had with the ARB diff is that I had an excessive runout on the ring gear after installing the gear on the ARB diff case. This dramatically affected the backlash. The backlash changes with the ring gear rotating with excessive runout. Who installed the ARB locker can imagine what pain is to put the gear ring on the ARB diff case (heat the gear in the oven, apply loctite, torque all bolts to 60Nm and then additional 37° of rotation – and do this without a solid 8” vise attached to a solid workbench). And I had to do this three times because I thought I had some debris between the gear and ARB surfaces. I turned out that the ARB itself (without ring gear) had significant runout! I put the ring gear in another three positions (yes, still had to heat the gear and torque it) until I found the best spot where the machining errors on both parts somehow cancelled instead of adding to more runout. I ended up with 0.001” total runout vs. ESM max limit of 0.0031”.
My advice for future ARB installers: Always check the runout on the surface mating to the ring gear of ARB differential case before installing the ring gear. This will give indication if you need to find the sweet spot and will save you time of applying and removing loctite from bolts and holes every time you put the ring gear.
One more advice: If you are married do not put the oily ring gear in the oven. The wife does not appreciate the smell of the burned oil coming off from her new kitchen oven. I would recommend getting a large pan and put it on the grill (put water in the pan!!! and then before putting loctite, blow off the holes with compressed air)