so that will open the gui on the client side that sets music, next you need to find the servercmd that is called when the client clicks send after selecting the music so you can package it to intercept the data you need.
I also suggest adding a timeout in case the client cancels, then like twenty minutes later sets music normally on a music brick, so that doesn't also trigger the server wide music
additionally, if you are simply forcing the wrench sound thing open, there will be no wrenchbrick, so line 5 is not needed I believe