Hi Angier,
      Glad to hear that we both stopped reading the manual years ago. ha  Marv's reply was pretty accurate.  There is enough hinge friction there to mess up your balance.  And yes, my hinges are perfectly aligned. ;-)
       Using the KISS method, I simply put a few phillips screws in a 2x4, and ran safety wire from the elevator hinges to the screws.  Once the elevator is hanging, the hinge friction is eliminated and can be balanced more easily.  Also, keep in mind that lead dust is toxic stuff.
        Regards,
                       D. Story, ATP