How to wire COLD on 24 pole attenuator?

I have a 24 pole ELMA rotary switch for volume. My preamp schematic shows the cold wire from RCA gnd lug should run to MUTE on the ELMA switch. The DIY amp I bought has NO wire in this position. If I want to run cold wire from switch to RCA gnd, where do I wire it? I don't see a MUTE on switch? This is a TVC. Thanks!