E37 E85 Tune

I cant find any real information on this but it seems like the E37 is capable of flex fuel without the sensor. I have an 07 2.2L HHR that I would like to make flex fuel if its possible to do without adding the sensor. She gets decent mpg now but I know from experience that a proper pump gas E85 tune is a lot easier on the wallet. I see where the 09's got flex fuel and they do not use a sensor and I believe they are both E37's so I assume its just a matter of if the drivers were installed in the 07 PCM.

iirc you can wire one into the correct ecu pin, enable the flex fuel toggle in the ecu and then make sure the flex fuel codes P0178/P0179 are activated and it should start working. dont quote me 100% because its been a while since i dabbled in the conversion.
just remember to start looking at your pe enrichment table in terms or lambda ratio once its enabled.

lambda (1.0)/ enrichment value(1.xxx) = lambda target