I would definately eat some carb the night before, and I would substitude some of the pasta with atleast one baked potato for potassium. I would also eat a banana before the race, and even one cliff bar.
I have not read this entire thread so don't know if your race is an enduro or a hare scramble. If it's an enduro, I would definately eat a banana during each fuel stop. And ofcourse hydration goes without saying, but drink often...don't wait untill you're thirsty to drink because for some that already means dehydration.