I am unable to give dimensions, but with the Balance Beam used with the Girdraulic Fork the back edge edge of the beam is essentially flat across the back edge, with the balance beam used with the Brampton Fork the tapped adjuster ends are gently curved forward, starting around the halfway point between the pivot point and the adjuster thread, difficult to explain, but once you see one you will understand what I am trying to describe.
I have just checked Know Thy Beast, Edition 2, Page 29, it states the beams are the same, but on the Brampton fork the outer ends are bent forward by 15 deg. to clear the bottom fork links.