Jmccreary

When the AC is on in my '80 there is no air blowing out the vents. Cold air blows down at the floor outlets, but non out the vents. So last night I checked it out and found that the tan vacuum line coming from the climate control does not hold any vacuum. This is the line that supplies the actuator which controls the vent door. I guess the actuator is bad. The problem is that I can't located the darn thing an I suspect that it is tucked way behind something under the dash. Has anyone ever replaced one of these actuators and if so can you tell me what the proceedure is. Do you have to take the whole dash appart?

Thanks
John