[Phippsy81]

I did this the other day... warmed up the car a little (the valve won't open immediately from a cold start) leave the car running then change to sport in idle, disconnect the plug. That's it.
Now you can turn the car off and you can physically see the valve still open on the RH exhaust. (330i)
I then covered the plug & port with a finger end of a black latex glove and insulation tape.
Zip tied the plug/lead to the side of the port on exhaust hanger.
Very simple to do.

It's louder on both cold start and when running in Comfort, but without so much of the burbles of Sport/Sport + (I expect that's down to throttle/Fuelling mapped for this mode)

I'll try and get a photo and video later if possible and post back.