a substantially horizontal hitch frame having a front end with front end effector to mount a plow, and an opposite, back end;

a lift frame pivotally connected to and extending vertically from the back end of the hitch frame, and having a back end effector for mounting to a vehicle;

an actuating system connected between the lift frame and the front end effector for raising and lowering the hitch frame and plow together relative to said back end effector;

wherein the back end effector includes two substantially parallel, spaced arms extending rearward from the lift frame for mating with respective spaced guides on a vehicle mount frame as the vehicle moves toward the back of the hitch frame, and two spaced latches for engaging a latch bar on the vehicle mount frame when the arms are fully mated with the guides;

each latch being rotatably connected to the lift frame and comprising a recess such that in a first rotational position the recess faces rearward for receiving the bar as the vehicle guides fully mate with the arms and in a second rotational position the recess faces vertical to capture and prevent the bar from moving horizontally out of the lift frame;

a latch handle extending from at least one latch, for rotating the latch between said first and second positions;

a stop surface on the latch remote from the recess;

a lock block supported by the lift frame, and abutting said stop surface to prevent rotation of the latch when the latch is in said second position;

means for selectively holding the lock block at said stop surface;

a lock handle operatively associated with the lock block, for selectively pulling the lock block away from the stop surface;

whereby an operator can operate the lock handle to pull the block away from the stop surface, thereby freeing the latch to rotate from said second to said first position;

an intermediate region between said ends having spaced apart, rigid beams;

a box frame having generally opposed, rigid walls overlying respective portions of the spaced beams;

a jack tube horizontally spanning and rotationally supported by the box frame walls;

a jack leg extending transversely from the jack tube, rotatable with said jack tube between a retracted position substantially between the box frame walls and a deployed position substantially vertical below the jack tube;

an elongated, rigid actuator slidable obliguely between the box frame walls and the spaced beams, having one end attached to the jack leg and another end projecting above the box frame walls;

means carried by the box frame for selective attachment to the actuator in (a) a first, retracted holding position, attached intermediate the ends of the actuator in which the actuator holds the jack leg in said retracted position, (b) a second, detached, actuating position in which the actuator is slidable between the box frame walls and spaced beams to rotate the tube, and (c) a third, deployed holding position attached closer to said other end of the actuator in which the actuator holds the jack leg in the deployed position;

a jack screw with expandable lift platform interposed between the tube and the leg; and

a socket at one end of the tube, operatively connected to the jack screw, for cooperating with a crank to selectively expand or contract said lift platform and thereby adjust the length of the extension of said leg from said tube.