Abstract: An apparatus for attachment to the body (240) of a vehicle (12) which has a front, rear and opposite sides and which has steerable wheels. The apparatus comprises a lower part (22) having structure (40, 48) for fixed attachment at each of the opposite sides of the vehicle. A first steering control arm (150) is pivotally connected to the lower part (22) at one side of the vehicle. A second steering control arm (160) is pivotally connected to the lower part (22) at an opposite side of the vehicle. An upper part (24) is connected with the lower part (22). A rack and pinion steering mechanism (10) includes a rack bar (180) movable axially in opposite directions to effect steering movement of the steerable wheels of the vehicle. The steering mechanism (10) includes a chamber (80) through which the rack bar (180) extends. The chamber is defined by surfaces of the upper and lower parts (22, 24).