[68 50th]

Just did this to my 92 Sport Truck. Spent Friday night and Saturday morning under the dash.

Removed glove box door and insert, control module and its support, blower motor/fan and its rubber cover, loosened the right side lower dash.

Loosened all screws from under dash and engine compartment holding the blower housing, tried to get it out but it was to little space between ac housing and kick panel.

Didn't have a 1/4 air ratchet but went over to a friend and borrowed one. It worked like a charm to use the method described by ChevyTech.

Many thanks to ChevyTech and others for sharing your experiences.

Have a question though.
What is actually operating/controlling the recirculation door? There is no button or anything to select recirculation or outside air like I have seen in other cars/trucks.

Thanks