im going to give this mod a shot.
i used the ziptie method .
the trunk/carpet panel in the video above is different than what i have in my n55 135i. The carpet piece removed ONLY gives you access to the tail light connections and you would have to remove the whole trunk liner to get at the solenoid for the vacuum line.
I took the tail of the ziptie and looped it through the vacuum line to prevent the ziptie from slipping off. It also allows more room to remove it if i want.
here is a picture of what it looks like.
This "Blip/gurgle" is now noticeable which iv never heard from my car before
I do a lot of in-town driving so i will return with my finding after i drive around with it for a couple days.