Just installed a Rough Country 3in lift. Love it, rides great! Took some work getting it done. Rough Country has a pretty complete video on the install. Helped a lot. Took 8hrs, including a trip to Home Depot. All four rear shock upper bolts broke. Had to drill them out. I expected some issues. All in all, a great kit.
If you're gonna do it yourself, you can save a little time by leaving the rear spring in the vehicle. I removed the clips and center bolt and added the add-a-leaf while the spring was still installed. C-clamps are a must. Many YouTube videos talk about how hard it is to remove the springs due to age and rust. Anyway, might save you some time.