No real news to report. I've driven over 50 miles now with the gasoline/acetone mixture in my tank, and the Jeep seems to be purring along fine. I haven't noticed anything quantifiable as far as differences, but the engine does seem to run a bit smoother, especially on acceleration. Not more powerful; it just seems like the engine isn't working as hard to do it's job.
This is not measurable, I realize, and it's entirely possible that I'm dreaming the whole thing. I wish I'd have done some measuring before I started experimenting. I'd like to see if there was any difference in idle speed, acceleration, etc. so I could have some immediate results.
As it is now, I'll have to wait until the next fill-up, which could be a while, especially if the experiment goes well.