for the amount of time it took them to do that they could have gone to autozone bought some ubolts, made their own flip kit out of a few pieces of 1/4" plate, a cutting torch, and a mig welder and gotten LOWER than that...
I have seen that exact mod before! Except it was on a lifted chevy same body style. He made shackles and hangers that were no lie, like 2 feet tall. The truck was huge but you couldn't have paid me enough to ride in it.
*edit* I like how he has more holes drilled in case he wants to make it even lower.