I presume that the fuel pumps, lines and seals may be not compatible as well. How about the injectors?
Tank shell and some lines are compatible, but pumps, wiring, some plastic, seals, and check valves are not compatible with ethanol or methanol. This is why we laser scanned and reverse engineered the stock tank to design a multi-fuel compatible race cell.
As to the stock injectors... I'd guess they are but the o-rings are not. The 1000cc ID injectors we use are compatible. We also machine the intake manifold for ID 2000cc injectors that are satisfactorily acceptable as long as no water is in the fuel system. Basic alcohol fuel system maintenance.
Same as why we designed our GT Mechanical fuel pump system. It is compatible and delivers the volume and fuel pressure needed for higher hp and or alcohol applications.
Cheers