i agree, i have done many ring and pinions on many difrent vehicles, it is a very time consuming process. you will need some expensive tools(magnetic base dial indicator, bearing press or arbor press, micromiter) not to mention alot of other tools(some times a case spreader is needed makes it easer) getting your pinion depth and your backlash set up correctly you will be pulling the carrier and pinion out and putting them back in many times to get the contact pattern perfect and the baclash within specs, if you are a decent machanic take your time and dont get frustrated, one time it took me ten hours to do a ring and pinion other times it lined right up first try and only took 2 hours, here are some tricks to make install go easer
take off all the old bearings very carefully off the old carrier and pinion, grind off the inside race of the old bearings so they will slide easely on the new carier and pinion, use these as set up bearing so you wont damage the new bearings pulling them on and off to change shim thickness
mesure the curent shim thickness used on the old pinion and carrier and use this as a starting piont to find the new thickness you will need, most times it is very close to the new thickness needed
reuse the old crush sleeve and pinion seal untill you have everything within specs only on final install use the new crush sleeve and seal.