Modding my Telefunken echomixer plse advice

Hi all, I want to be able to switch off the direct sound from the echo mixer. Also, i want to route output channel b into c (through a switch), so i can really drive it. I attached the schematics, can someone advice on how to do this? my guesses: 1. dry off switch: place a switch after C12? 2. reroute output to input: route the output of w7 to w11? is it as simple as that? thanks!