I didn't do a full writeup, but here's mine:
http://www.toyota-4runner.org/5th-gen-t4rs/92013-antmans-thread.html#post806239
Some tips from my experience:
Take the spare tire out- gives you much more room to work ( I wish I would have done that first, before struggling for 1/2 an hour!!)
Once the truck is on jackstands you can remove the shocks and swaybar links and jack each side of the rear axle individually to get the springs out easier. Depending on how high your jackstands are, you may need to remove the rear wheels to allow the axle to drop enough. The stock suspension has an amazing amount of articulation IMO! Watch the brake hoses and ABS wires!
I found a sawsall worked great for cutting the bumpstops. Just be careful.
I ran the air line along the axle and strap tied it to the flexible brake lines and their bracket to transfer from the axle to the body. Basically I followed the factory brake line routing.
When you drill the hole in the bottom of the spring perch, make sure you debur it with a file, and spray some paint on the bare metal.
I covered the air line with some thick wire loom anywhere it could rub metal. No leaks yet!
Make sure your springs are seated correctly. I had to go back and fix the passenger side after I was done, as it shifted slightly out of place.
Others said they compressed the bag and pushed it between the spring coils, leaving the springs in place. I couldn't get that to work! Maybe it's worth at least a try though...
Take your time- you will love the results!