Well done for toughing it out.
At 6ft there are a lot of drink stations so no need to carry water in my opinion. Just extra weight to carry up hill.
Most important thing is to find some food/gel you are comfortable with by training with it regularly.
There is a great atmosphere at 6 foot - you'll love it!
Well done Blair - I agree with Rob on the water carrying - the drinks are very frequent. if you're in wave 2 or 3 it'll be worth practicing running fast downhill on a rough fire trail to get in a good position at the top of the stairs, you'll likely be walking down the stairs but it'll get you in a better position to run when it flattens out a bit.