I looked into flex kits, for another car, a number of years ago, but at the time my car was to old to safely run on e85 and the supply of the fuel was very rare so I stopped looking.
I particularly like the idea of getting more power just by putting a different fuel in the tank.
I look forward to finding out how you go with it, when you find a suitable flex kit.
I think you two are referencing 2 different things.
@GT2Crew isn’t looking for a FlexFuel kit, but rather a Fuel-It FlexFuel sensor to integrate with the JB4. I doubt the search for a used one will bear fruit, but there are new ones that can be purchased.
I believe @Luc343 is looking for something that doesn’t exist with the Stinger, and that’s an option that would automatically run a more aggressive setting based on the presence of E85. I don’t believe this is likely to happen without an accompanying tuning device.