I am no expert on carb design, but the gas carb should be closer to start with than a methanol (alky) carb. Remember if gas is 100%, E85 is about 135%, and methanol is around 200%. So the boosters and passages in the metering blocks will be too large and slow the fuel down in an alky carb running E85 (if you can choke down the total fuel flow).

Things like the main well dia, cross channel passage dia, booster fuel flow channel dia, etc.

I have been talking with guys on e85forum about my 950 carb boosters. On gas they are 0.156", an alky setup might be around 0.190", I am having a shop put 0.170" boosters in for 2009.