I am at a loss as to why you would want to alter the width of an antler spread to be shorter. If you do, it is no longer representative of the animal in life and I also think it would not look right. Technically, it is not all about the "antlers" the spread takes into account both the width of the skull as well as the combined length of both antlers. You may as well just pop off both antlers and stick them in holes in a plaque as do what you are thinking about doing.