Has anyone with a 4-6" lift installed this upgrade? If so, what are your thoughts. I did a search but came up empty. I guess my biggest concern would be that of the pitman arm. Some folks have replaced this with the newer design, while others have not; however, these have been on stock or leveled trucks. That i am aware, Superlift does not offer the arm with the improved angle/geometry and am curious if i can use what i currently have. TIA