Need Help With Building DIY Grounding Cable

Hello,

I am planning to build a DIY grounding box. I am planning to connect my DAC and Integrated amp to this grounding box by connectig the unused RCA input terminals on the both. For this I need to create two cables with Banana at one end and RCA at the other end so that I can connect them via speaker binding post on grounding box.

I need help with how & where to attach (solder) the cable on RCA socket.

I also need help in understanding if I can connect both L & R RCA input sockets on same amp to same grounding box (assuming I am going to solder the wire on the shell/-ve part of RCA connector)? Also Can I similarly connect all unused inputs on DAC/Amp to grounding box.

I understand attaching multiple inputs to grounding box is not going to amplify the effect & I just want to do it for protection of those input terminals.

Regards,

audio_phool