I've just reread the old book on converting a VW to alcohol (80%) and here's the top issues.
The most daunting points concern 1) cold-start system. 60F or less is "cold" to alcohol, and you need a gasoline or propane starting system to get going. Quite involved. 2) huge modifications of the intake manifold to keep it hot enough to support adequate vaporization. Just forget the stock system for doing it. The mods a huge pain. Or run 1bbl duals on short manifolds (recommended). 3) you know the rest - requires electronic ignition, 10 to
11:1 compression (meaning you can't go back to gas), overjetting, changing the behavior of the accelerator pump, bump the timing, and get about 30% less mileage.
So... you want to still do it?