What about this new Ethanol E-15?

The only real part of the car to be concerned with first off damage wise will be the valvetrain. If you step up on running a more modern setup this should offset most of the issues. Other things wil go wrong down the line but the upper end takes the hit first. Just think what kind of garbage has been coming out of gas pumps the last several years (you dont really want to know) and your car still runs. Make a couple of mods and just go about you business.