Can Submarine Pickups be used in stereo or summed to mono?

I would like to combine the sound from two of my guitar outputs into one amp – how can I do this?

Can the SubPro provide more than two channels of output?

With the SubPro, can one string be routed to two outputs?

What are the three switch positions on the SubPro?

What are the three switch positions on the Submarine?

What sort of interface should I plug the 6 outputs of the SubSix into?