AC Vent selection control problem

Hello, I sold my father my firebird last year and I knew the climate control was working properly. I know the vent selection is some sort of vacum system to get the vents to open and close. I can not find where it may have gotten unplugged from or whatever. My father has been putting chrome wire looms over all the cables, so I think he may have pulled it off. Are there any other locations that this system connects to other than the control unit and near the computer


Thanks in advance

I guess you have seen this (http://shbox.com/1/4th_gen_tech2.html#HVAC_vacuum)? There is also a vacuum manifold connection under the RH side of the dashboard. (Multi-colored hoses from the mode control switch to the hose that comes from the engine compartment)