E85 is a very different fuel from ~10% blends and requires a number of modifications. If you were going to convert you might as well go 100% ethanol, since it's about that much of a change. You'd be looking at mostly the fuel delivery system, all Viton o-rings and seals, higher-flow injectors, all stainless fuel rail and possibly ECU programming.
I've looked extensivley into a 100% ethanol conversion on one of my VX's or XR4Ti's, but can't start until our new home is built which will give me the room to setup for ethanol production.
Here's a good page with a lot of ethanol and E85 info: http://journeytoforever.org/
