bounce to track error or operator headspace

I've got two guitar tracks. The audio does not overlap on them. I want to bounce them, to one track. I know I could just drag the clip from one track onto the other, but I'm trying something new.
 
When I select both tracks, and then use "bounce to track", even when source is set to tracks... I dont get one track with everything on it. I get two new separate tracks.
 
Anybody have any idea what I'm doing wrong?
 
Rod

Destination: new track -
 
but instead of making one new track, it makes two

that worked! thanks! routed the tracks to a new bus, selected that new bus in the source field, then selected new track. It makes a new stereo track, combining both the old ones.