Well here is my theory, I was running Rancho RS5000's all round on my sierra now they have been a great shock good offroad and on but because the rear shocks are inboarded 45deg. they give great flex on tracks and what not but when Im on the road because the shock is only doing half the work, e.g when the springs compress say 1" the shock is only traveling half a inch the back as well as being SPOA can get quite boatish and wallow around or rock back and forth in change of road conditions. So I got some Adjustable RS9000X's for the rear and set them on '7' for the road now the rear seams to ride alot better if not feels more equal to the front, and it feels alot safer on the road now. Now I just need to test them out on super soft in Off road stuff.
Adjusters in to hopefully stop them being knocked off..........
Shiny red boots
... But seriously its very nice, I would like to know about your 'A' arm setup. The Inverting was done how a mate has done his. It also rolls around as I dont run any sway bars either. Any how I have had the 4by up a Ramp and on full up travel I got a spare inch or two its the down travel I need them for mainly. But Ill look at moving the shock mounts up top a little further out and a little higher and see how I go, Im playing around with a few other things at the moment so see what happens.