Your glove box or console don't need to lock, but they do need to be closed. You are not required to notify, but in my opinion it's better than opening the glove box and having your Glock fall out. Personally, when I carry in the vehicle as opposed to on my person, I keep the registration and insurance seperate from the gun and wouldn't bother to mention it's existence.
Here are the answers to all your questions, specifically 16-23-20(9)(a) and (15);
Enjoy your vacation!
Almost forgot. If you're on vacation, you might be using a motel/hotel. Take a look at 23-31-230;