From what I understand, you cannot run E85 with the 2 degreee advance. The ECU has to change the timing to account for the higher octane of the E85.
I don't know about your area, but here E85 is only $.30 cheaper than regular unleaded. That is about half what it should be to break even after the loss of fuel economy from using it. At this point, it will cost you more to use it over regular unleaded.