Set it to gasoline. As I mentioned in the PM, the sensor reads lambda so as long as the gauge is set to gasoline, shoot for 14.7 as stoich just like you would if you were tuning with that. NOTE: when the gauge is reading 14.7, that's because the sensor is reading 1 lambda. It is doing the AFR calculation for you already (obviously). Though the gauge is reading 14.7, the actual "true" ratio in the combustion chamber is really going to be 9.7:1 (or whatever the accurate value is).
It's confusing to understand why it works that way, because it really don't make too much sense at the beginning. When I first swapped to to E85, I spent a good bit of time trying to re-write the algorithm in my tuning software to display E85 AFRs until I realized that I just still shoot for the same AFRs as I have been.
So, again like I mentioned in the PM, if at say 18psi you were shooting for 11.7:1, then with E85, make sure that gauge is reading 11.7:1 as well. Also notice that while gasoline and E85 lambda values are the same stoichiometricly, they do differ in their lambda max rich and max lean power values.
Maybe someday in person I can explain it to make more sense.