John,
Let it all slide over you.
You've made all the decisions you get to make, and you've prepared as much as preparation can help. Now, it's up to those surgeons and nurses to do the job well.
It goes quickly, once it starts, and if you don't think about it a lot, it will be over in a blur. For me, the operation was everything. When I woke up and realized I was still alive, I honestly felt no more fear. Annoyance, a few times, but no fear.
I hope it goes as well for you as it did for me. You will be on my mind tomorrow as I arrive at work at 7:30, a half hour before you go in.
Very best wishes,