Blue Ox Sway Pro Installation

I believe that when it says to make sure the vehicle is level means that the drop when the trailer is attached should be about the same all around. When I installed a Reese hitch one time I measured the height from the ground to the rear and front bumpers before and again after. The difference in drop front and rear was less than a quarter of an inch so I called it good and it work as it was supposed to. As someone else stated you just don't want the headlights pointing to the sky.