I think you would be better off buying a new E85 carb as all alcohol base fuels eat and corrode aluminum
I've been racing on pump 85 for 6 yrs. now I had A.J. Casini at Bob George racing(206-472-7412) convert a 1150 CFM Holley I had in hand to E85 back then.
E85 motors consume around 30% more fuel per run, my car was had a blown alcohol(methanol) B1 motor in it before I bought it and put in the bracket 400 stroker motor on pump E85. It has a 7.5 gallon fuel cell mounted in the front of the car and no radiator It does have two small oil cooler running coolant through them for the cooling system. The motor runs very cool most of the time with this set up
Let me warn you that once you get the E85 carb tuned in correctly it will vary very little from the first run of the day to the middle of the day and on into after sundown, maybe as little as .0005
Good luck on your deal