Does anyone know if the front sight ramp, from the "old" style vs the "new" style, are interchangeable? I tried removing my front post, to install a globe front sight. It won't move at all! Not wanting to damage the original (late 50's vintage) parts, I thought that I'd just put on a new ramp and globe sight. The angle/slope of the two are visually different, but I don't know about the screw hole spacing. Thanks! EDIT: 1960 (T) serial number.