Blend door actuators

[Banshee365]

My buddy has a job 08 that appears to have a bad blend door actuator for the drivers side. He has dual climate and the left side blows cold unless it's turned all the way up. You can hear the blend door actuator jiggling back and forth like it doesn't know it's position. It isn't working correctly and apparently it is a common issue with a TSB associated to it.

Where is the blend door on this truck? Does only the glovebox need to be removed? I saw some vague instructions talking about removing the audio control panel. Would that be the radio in the center of the dash? Does that really have to come out or just the glovebox? Going to try and fix this for him as he has no more warranty left.