[RDrancher]

Thank you for the detailed photos of the rear suspension.

Looks like factory shackles to me too. I'll be flipping the rear on my Sub in the near future and have a set of air shocks for carrying loads. If it's too low (unloaded) without air in the shocks, a set of lift shackles or a notch will be in order.

As you may already know, with inverted lift shackles the amount of lift is halved when measuring eye-to-eye against your existing shackles. 1" shorter=1/2" lift, 2" shorter=1" lift, etc.