Keep up your aerobic rides. I echo all the other posters about not being able to do much about it now. This is where all that riding will translate into benefits. Dependent on how much you really rode in the past two months and how - will show up on a ride like this. Personally I think you'll be fine. You've got almost like 2000 miles under your belt.

Take the hills firm and steady - and NEVER NEVER try to redline it. You will roast yourself. Just pour the power accordingly to slope.

Just do it.

Good Luck!
-Peter