How can I shield cables from interference?

What about running a separate ground cable from the shielding near the male termination, instead of removing the plug and soldering to it?

I guess you'd have to hack off the male ends of your power cables and install a new one in order to do this, right? What kind of solder would work best for a fix like this? I'm hunting for the right kind of techflex to do this with - one of their reps told me only the conductive nylon would work for this kind of application...