IF the ethanol is seperating out, there is already a big charge of water in the fuel to begin with.....
On you tube there is a guy who removes the ethanol from gasoline. The first step is to add in enough water to saturate the alcohol molocules, so they mix with ony the water. Alcohol in dry fuel will keep water out. But when enough is present, the only reason it could seperating out is there is lots of water already in the fuel....
Fuel lines are all compatable and have been for years. So are carberator kits. Here in Iowa we've been using E10 since the late 70's. Initially we had issues with crap the ethanol would disolve in the bulk fuel storage tanks.. Eventually this cleared up. Currently lots of us are using E10 in sleds with out issues. Synthetic oils may help make it work too, don't know for sure.
Regards, Kirk