Anytime I'm not sure if a motor can handle my 17 hour trips i always take it out and back at least an hour each way on the freeway, which is good cause anything cool is at least an hour away from this craphole. If a failure doesnt occur during that trip then there is no reason to expect a failure on a longer one(but that doesnt mean dont plan for it)The only real tip I can give you is do not schedule anything for that first day or so until you get there, that way if you need to stop and take a break, or even stay the night if you get tired, then there is nothing stopping you. Just cause google says 9 hours, dont expect to arrive 9 hours later.

As for riding at night, I wouldn't do it on the first trip, go the day before if you have to, then you dont have to worry about fatigue, and if something happens to the bike, they will only be a few hours behind to help you out. Also take the little lady on your long test ride before she makes her decision, running around town and buzzing down the highway for hours will affect you passenger differently, so let her feel it out first.

Sounds like a really fun ride, and if you want to ride on the beach, just try this