Setting up gears takes a few special tools that are not normally in the average tool box. Off the top of my head you will need a press(although I setup my first rear end by heating up the pinion bearing in the oven and dropping it on,) dial indicator, micrometer or calipers, inch pound torque wrench, foot pound torque wrench, setup bearings for the pinion(makes life easier), bearing separator, normal hand tools, plenty of extra shims, and most importantly PATIENCE. You really don't need a pinion depth tool but it would speed things up a little quicker. I usually measure the old pinion and the new pinion and add or subtract shims to get the same thickness. That will get you in the ballpark. Then assemble, mark the ring gear and check the wear pattern. Then add or subtract shims until the contact patch is in the center.
It is not rocket science but if you have never done it before I advise enlisting the help of someone who has. Like I said, patience is the most important part. The first set I did I counted 7 times that I installed and removed everything before I got my pinion depth where I wanted it. That is also where the setup bearing comes in handy. If I would not have spent the extra 10 minutes to clearance the old pinion bearing so it was slip fit I would have pulled my hair out separating and pressing the bearing on 7 times.