I have a class III hitch, maybe from hidden hitch? Anyway, I had planned on mounting this in the same manner (by dropping it 3/4 of and inch down), only I was making a plate from aluminium in order to allow the hitch to contact the unit body of the edge completely and not just by the surface area of the nuts. Since we just purchased an explorer with a tow package I no longer need to do this. But as i stated in a different thread, 3/4" will bring you under the rear bumper valance.