How much does it cost to replace the ac air delivery mode door actuator chip?

I have a similar problem with my '96 Olds LSS. Air comes out of the wrong places and at the wrong temperatures, though not consistently. Can the actuators be checked without tearing down the car to get at the "black box"? If so, is the $700-$1K cost cited above a part cost or total cost? How much labor is involved in replacing the actuators? Can a DIY guy check these, or does it require specialized test equipment? Thanks!