[hemi43]

The only difficult part about doing diffs is setting up the pinion depth. Actually, it's not difficult at all. You don't need any special depth setting tools or gauges because all this will do is over complicate things.
It looks like you damaged the original inner pinion bearing taking it off, so buy another one because they are cheap. Take this bearing and hone out the bore so that it slips on and off fairly easily on the pinion. You can also use an abrasive flap wheel to do this. You can now use this bearing for your setup to determine the shim pack needed for getting your proper pinion depth. Once you get a nice mesh pattern, take off the setup bearing and press on the new bearing that you got in your kit. Take your time crushing the collar until you get 15-20 in/lbs of resistance, then reinstall the carrier and set the backlash. I've done it like this for years and it makes the job so easy.