Where is the vacuum blend door actuator location and replacement instructions?

If you put it back on you can cheat a bit, cycle through the vent positions while you watch the actuators with the engine idling. If the other ones move as they should just swap the vacuum line off one of those to the questionable part. If it starts moving the problem isn't the actuator but probably the control head or the line to it. Another test would be to select the vents and pull the line off, put your finger on the line, can you feel a strong vacuum? If yes then it's the actuator, if no it's the controller or lines.

You're welcome, If the testing shows you which parts are bad even better.

Great to hear, where was the leak?

That's how they like to hide. Makes it so you can't hear the leak. Good to hear it wasn't something worse. Thank you for the update and for using 2CarPros.