I'm in the process of removing my engine and I can see how to disc the brake booster vacuum line . I did a search but didn't find anything useful. Im stuck on this

 

Press the brake pedal a few times until it becomes hard to push - this alleviates any residual vacuum and will make disconnecting the line easier.
In your pic, squeeze the sides of the fitting while you pull it apart.
edit: sometimes it helps to push the line into the fitting, then squeeze, then pull.

 

I'll try that in the morning. Thank you