Nancy,
Let me echo everyone else’s sentiments. Keep in mind you will be nervous until you get there and there is little you can do about it. Even if you knew EVERYTHING, I bet you would still be nervous. I know I would be nervous. But, I know you will do great once you get there! That’s why you are going, to learn. You’ve got the best teacher. He’s seen a horse like yours dozens of times and can help you fix him.
Keep spending time working your horse between now and then and I know you will have a fantastic time!