I know this has probably been covered already but I thought I'd type up a thread anyways on my experience with removing the blocks and whats needed. It took about an hour to do by myself in the driveway. Only tools needed were 21mm wrench, 21mm deep socket and either ratchet or breaker bar, washers (optional), pb blaster or wd 40, a jack and a jackstand. My truck only has 14000 miles so the bolts were not on there overly tight or caked up with road grime and debris.
Install was easy, do 1 side at a time.
1. Soak threads of lower shock bolts and u-bolts with penetrating oil.
2. Loosen all 4 nuts on u-bolts and remove them, loosen the lower shock bolt/nut and remove.
3. Jack up enough to remove block, and remove the block.
4. Slowly lower the truck back down and locate the alignment pin into axle mount pad.
5. Install u-bolts and bracket
6. (optional) Install washer to act as spacers on u-bolts. Most say that they have no probems and I don't doubt that, I used them for added insurance and piece of mind.
7. Equally tighten all u-bolts and reinstall shock and bolt.
8. Repeat on other side.
That's it in a nutshell, I didn't even remove the wheels to do this and it literally took 45 to 1 hr in my drive way.
Hope this is helpful, Its a basic and easy procedure, just wanted to share.