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Sorry if I missed this part, but I've been skimming at work (distracted a bit as I go).
I have yet to see anyone mention a change in tune. Tuning is key to running safely with heavier modifications, like running 100% e85/ethanol mix, as well as increasing your compression.
If you don't offset significantly higher compression by lowering timing and altering your fuel map, you'll risk detonation, causing you much more headache (and cost) than you'll save.
In terms of 100% ethanol, doesn't it use something like 20-30% more to run the motor than just using regular gas? This is why I mix it in (about 15% mix) in my fun car, to take full advantage of the detonation proofing (or at least, resistance) that it provides, without increasing consumption significantly - I can safely run fairly high boost, make plenty of power, and not worry about putting a rod through the side of the block.
I'm asking, because I don't know for certain, but I don't think it's as simple as increasing your compression and running pure ethanol - I think you need to alter your fuel curve as well right? Timing can stray into the advanced, but you still need a proper tune for it to run "right." Also with older cars (pre 1994 or so), you should probably consider replacing your fuel lines as well, since older ones are more prone to breaking down and falling apart with a little ethanol action.
Just my .02 cents, and since I'm not too knowledgeable about the fine details of tuning, but it seems that you'd want to get a wideband, and see where you're running (at the very least).
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