I googled and found this, not sure if you caught this.
"Ethanol And Effects On The Fuel System
Q. Hi Vincent, I really liked your writing on ethanol, you really know your stuff. I've learned a lot. This is the best introductory write-up I've come across. I am looking into getting a Fiat 126BIS, and running it on ethanol. I hear that ethanol can rot rubber components in engines; gaskets etc. since they are derived from crude oil. Ethanol And Effects On The Fuel System
Some refer to it as a sort of "drying out" process. Is this so? Also, does ethanol damage catalysts?
A. A 10% blend of ethanol and gasoline will not harm any engine or fuel system component. However, the ethanol has a cleaning effect that will remove rust and other junk from the fuel system. This necessitates frequent fuel filter changes until the fuel system is cleaned out.
No modifications need to be done to allow an engine to run on a 10% blend of ethanol and gasoline. There is, in some areas, an 85% blend of ethanol and gasoline that does require engine modifications.
Actually there is no rubber used in the fuel system. All the fuel lines are made of Neoprene which is impervious to degradation by gasoline or other additives."