It's just one day... even less than that. You're the expert and you know a lot more than you think you do. The finishing line is just ahead. And, if all else fails... just picture your panel in some vulnerable position... like on the loo... at the end of the day, they're just people, like you... maybe, yes, with a little more experience, but not in your exact area of expertise...
More and more I'm realising (having just been an examiner albeit at a much lower level) that good examiners (if you've chosen well) are good people, interested in new ideas coming through, looking forward to having a good discussion with a candidate... try to think of it as an opportunity to talk about your work with two people who have actually read your thesis and are interested in the outcome. :-) That said, I suspect I'll probably feel exactly the same as you feel when my turn comes, in a little over 6 months time, I guess. Go for it... nearlty there and it's what all of this has been about for you... (up)