An apparatus and a method for accurately and repeatably positioning metallic parts comprised of variable length extrusions and shaped sheet metal in a modular die system that forms a joggle in the metallic parts. The apparatus of the present invention is comprised of a standard joggle die system that is currently in use in the art. The apparatus further includes a movable back gage assembly that works in combination with the joggle die system to allow an operator to accurately position the workpiece between the joggle dies at a preselected position. The back gage assembly is movable in both the horizontal and vertical directions. The back gage assembly moves into a stored position away from the working area of the dies to permit the joggle to be formed in the workpiece. The back gage assembly can then move back into the working area to accurately position the next workpiece without the need for further adjustments.