W123 Defroster Actuator Removal

[dieselpilot]

I am working on a 1982 300D Turbo. I have traced a vacuum leak in my ACC to the defroster vacuum actuator. I am having a hard time removing it. It is the type where apparently you depress a small tab on the top of the actuator , then twist it to remove it from it`s bracket. Is there a trick to depressing the tab- its tough to see/feel. Also I`m worried about disconnecting the pull down arm of the actuator from the defoster linkage. It looks like it would be easy to break the plastic piece that connects to the actuator. Any/all wisdom from those who have done this procedure would be helpful. The archives a little help but not enough. Thanks.

PR