Product review (1 stars): GE Engineers asleep at the wheel
Don't look too close, the GE engineers are sleeping.  On a perfectly level floor the unit will have a distinct tilt toward the rear.  The back is on non adjustable rollers and the front rollers are used to make the height adjustment.  the problem is that even when fully retracted, the unit will be three inches away from the wall at the bottom while the top touches.  The adjustment will allow you to significantly increase this tilt but will not allow you to eliminate it.  see pics attached.  I ended up using 3/4' shims.  the floor is level and even if it weren't, with as much adjustment as is available one would imagine you could level the unit.  not so. I  verified this by having two different GE service techs come out to look.