I am level. Ideally, the front end should sit a bit lower than the rear end. (unless you want one of those cali looking pseudo baja trucks where the front end is 2 feet higher than the rear end, on an F250 no less). I can't tell you the ride difference between the 912s and the 919s, I put the 919s and Rancho9000s on at the same time. I would guess that setup gets you as close to factory teeth jarring stiffness as possible. When you do the springs, make sure you do the shocks as well, they are probably toast. Our OEM shocks are not known for their longevity. The good thing about the rancho9000s, if its too stiff for you, just dial em down to soften the ride.