have you put longer shackels on the front? ( most likely 8" lift /forums/images/graemlins/doah.gif)
removeing the leaf in the rear would give ya a bit more flex, or some one was talking about useing straps and chains to hold your truck down compressing the springs to the position you want and leaving it over a period of time. thuss makeing the springs sag.
/forums/images/graemlins/thinking.gifits a cheap way.