Brad,
I just picked up one of these 50# LGs myself. The angle on mine is aprox. 17deg. from the face of the top slide (further away on the left). I would be happy to take other dimensions or pictures if you need them.
I don't have much experience with this machine yet, but it seems to be in pretty good shape. My first project will be to make some dies for it. Good luck with your hammer.
Mike