Stereo is a complete waste of time in live gigs like this. No-one in the audience will notice, especially not when it's the first dance and people will be paying the band even less attention than usual. Maybe if you were the Foo Fighters and had a 12 gazillion pound touring rig, but for most of the gigs most of us are ever likely to play it's like tits on a bull.
If you were going to do it, you'd need both channels from the pedal going into a separate input on the desk and panning one full left, one full right. Having stereo split between FOH and your bass rig is not going to achieve anything other than a horrible mush on stage.