As others have said, you'll get a few glimpses of the fireworks, mostly at the start (after you go by Stitch's Great Escape, the TTA turns right and you can see the castle) and at the end (after you emerge from the tunnel). You'll hear the music at that point, but it's going to be faint (basically, you're hearing it from the speakers that are projecting the music into the normal viewing areas). It's an interesting view, but you really won't get anything more than a few brief glimpses of the fireworks.