Great question. I won't be able to acclimate the day before the race and the best I can do is backpacking overnight this weekend on 10,000 fts in a mountain in California. I will fly in Saturday afternoon, pick up my bib, eat, and try to have a good night of sleep before next day race. Like you mention, I will try to hydrate more, eat, not rush up in the accent. And take ibuprofen every 2 hours or more if necessary. What do you all think the chance of still having problem like AMS on higher elevation 12,000-to peak.