Join Date: Sep 2008
Location: Fruitland Park,Florida
The dial indicator is a tool that measures distances. It is set up will other accessories that hold the dial indicator in the correct spot to measure distances between parts, or measure back lash between gears.
I suggest doing a google search for step by step rear end setup. There are write ups and video's out there to help you. Also the 4th gen section has 94, 96, 98, & 00 f-body service manuals that you can read to get the procedure.
After that you can decide if you think you can handle the job, then go out and buy or borrow the equipment needed to do the measurements. Autozone and Advance auto parts lend tools, but I don't know if they have rear gear change tools.