I'm trying to determain if I have an original torque tube in my '39 1/2 ton. It measures 60" wide from hub to hub on the outside which is 2" wider than the front axle. The tires are tight to the fenders. The length seems normal but that could have been shortened. The spring perches also center on the axle and direct bolt to the springs unlike my AD which has a hinge system which offsets from the axel center. Is ther any difference between a '39 and '40?