6D electronic level in viewfinder?

I've seen words to the effect that you can turn on the electronic level in the 6D by somehow reconfiguring the DOF preview button in front to display the level line where the exposure meter normally is. I can find no reference to this in either the printed or PDF manual for the camera.

Does anyone know how this is implemented? Being able to see the E/L in the viewfinder would be very helpful, especially the default focus screen does not have a grid on it ...

Thanks much.

Check pages 61-62 of the manual. Haven't tried the VF one yet.
But from what it looks like, once you press the DOF button (after reconfiguring it), the level appears on the VF instead of the exposure meter.

Thanks! That did it - I didn't remember seeing this when I skimmed through the PDF file on the CD.