Thanks! A couple of changes - the early NYC bodies have a different shape (Like Smiert Spionam's beautiful guitar above), then there's another body shape that seems to appear around the move to Hoboken around 56, and then around '61, '62, the body shape changed to what you see in my pic, and those are considerably bigger ànd deeper than the ones before that - not a subtle difference. It does seem to be the shape Guild stuck with all through Hoboken, Westerly, and even Corona.
I have a late 50's X175 as well, and that has the smaller shape, bigger butt, smaller waist, and less depth to the body.