I bought a small ruler at Eckerd today, I think it was $.49. It had a hole in it near the top, so I figured I could mount it to my Great Planes Accuthrow meter, low and behold, it's almost as though the ruler was designed for this application!!! Another $50 saved by a little ingenuity..

Just remember the hinge line has to be were the bottom of the protractor is to get correct degrees.