Once you have the passenger headlight out you will see the black plastic box with a vacuum line attached to it. I just fixed mine this morning. In the picture is the area behind the headlight. You can see the T connector and the cracked hose to the actuator. Both ends were dry rotted. I also replaced the tubing from the T down to the black box. This fixed my cruise control and my AC vents. Before, AC would only blow out the defroster.
2001 GC Laredo 4x4 - Black
2001 GC Laredo 4x4 - Silver