Sliders will move the rear eye up an additional two inches. However, because of the arc of the spring, this only translates to .75-1 inch of drop at the axle. They also require periodic inspection as dirt, grim, and road muck can jam up the bearings used in them.
In an installed position, the stock style XHD springs should compress down to about a 2 inch arc. Whether or not this is low enough for your set up I don't know. There are any number of specialized spring manufacturers that can make the same spec spring for rate in 1" or 0 arc heights as well. Remember that there is a difference in free arch (unloaded) vs installed arch. A 5" free arch can install to a 1" position depending on the number of leaves and size of those leaves.
The easiest thing to do is simply install the rear suspension in its stock mounting points and put lowering blocks in it. Whether or not this is the best method for your application, I do not know.