Remember I am using a Andersen hitch and I'm going to raise the upper ball, which raises the pinbox. By adjusting the pinbox in the bracket, it will drop the whole trailer box lower over the pinbox, which lowers the trailer but not the pinbox. The key here is raising the upper ball to create more clearance to the bed rail.
The adapter has the ball forward of the pin by 4". Switching it around will move it a total of 8" which would be too close to the cab on tight turns. Also, it wouldn't change the distance from the pinbox to the bed rails, it would just move everything forward.