Blend door in 94 chev pick up

I get a clicking for about 20 sec around the heater fan when I turn the truck on and off. I've been told it's my blend door and I need to replace it. Can anyone give me an easy step by step to get at the darn thing? Do I have to pull the whole dash off?

I get a clicking for about 20 sec around the heater fan when I turn the truck on and off. I've been told it's my blend door and I need to replace it. Can anyone give me an easy step by step to get at the darn thing? Do I have to pull the whole dash off?

Check the actuator first.
Many times the gears strip in them.