I played with doing a shackle reversal for a while ... backed off ... for now.
First it's a major one way move. I'm sure it might be possible to undo but you have to cut off your front shackle hangers and *should* weld on the SR replacement hanger. Ugh.
Second geometry changes on axle articulation. Here I have enough knowledge to be extremely dangerous. If you are building for a dedicated trail rig ... Shackle Reversal is the way to go. If you rig sees way more asphault than rock ... be causious of a SR.
I have not excluded doing an SR in the future but I first wanted to do the lift and get use to the higher ride and larger tires before a SR.
Most likely too you will be playing ... "Which rear shackle length is correct ???" to dial in the correct vehicle rake (front/rear lean).
SR's are great but this is definitely not a trivial mod.
HTH,
Cahil