You almost need to know what you;re looking for in order to see it. the following pics might be helpfull:
With the glove box insert removed, the air mix door arm and actuator connection can be seen through the left hole in the black painted steel section.
here'* what you're looking for. You can see the actuator rod (threaded section) air mix door arm (yellowish thingamabob) and the connector (vertical white hickydo)
If the actuator is faulty, the rod and arm can be moved manually with a long screwdriver or similar tool but be carefull... if it is not the problem then you can actually damage it by manually moving.
Does your temp display still blink???