I have found for all of my early SS pins I need to put 3" legs on the back. I always put the leveler all the way out with just enough room to put a nut on the top and bottom of the leveler on the back legs. I don't trust the old, rusty threads with the leveler all the way out.

On the front I do as Hawk007 recommended. Move the nut on top of the leg and get an extra 1/4" to lower the front of the pin.

When I do this all of my early Bally SS pins are just barely at 6 degrees, which feels right to me.