First let me stress I'm no carb expert. If it was my motor and was going to run E-85 though i'd increase the compression first thing. You have to remember, E-85 has less BTU's per gallon than gasoline. It's high octane fuel and will like more compression which will offset some of the loss.
The 750 double pumper carb would be tough to beat. Also I would HIGHLY recomend a LM-1 meter, it will speed the tuning process and keep you out of trouble.
IMO E-85 will be becoming more common all around the country in the next couple years. Currently Holley and the other big carb companies haven't done any work with E-85. I think you will see this changing as they get more calls about it.Dave