Removing vocals

[mixerboy]

I'm sure I have seen a technique somewhere that removes vocals, the same technique as you get on those karaoke machine.
I have 3 tracks: vocalist 1, vocalist 2 and guitar. Unfortunately the guitar track was ruined by a dodgy connection and is distorted. My plan is to duplicate the vocal track with most guitar spill on it, remove as much vocal as possible and eq the guitar up. This was from a song writing session so I'm not looking for stunning results, just a bit more guitar. Any ideas?
By the way, are there any plugins that do this, searched through my waves plugs settings but could not find anything.