I want to raise the rear of my truck since it sits level to the point that it looks like the rear is slightly lower than the front, but I want some rake to my truck so I was looking at getting a couple of blocks to raise the rear end up.

problem is, I think I already have a lift on the truck? Is that what these blocks are under my leaf springs? This is a 2005 2500

If so would these blocks work to raise the rear end, because it looks like these would need to be stacked? like I think these blocks are meant for a stock height vehicle?
https://www.readylift.com/2-rear-blo...00-3500-1.html

How hard is it to actually install a rear lift? is there anything I need to worry about with making sure the axle goes back on to the truck perfectly straight?