Yes, visualisation is a good method to get the players comfortable with performing a task under pressure. I used it on some occasions, it is a topic in the mental game plan book I review.
you can "guide" the players through the whole event:
entering the stadium
enforcing the feeling of what went right so far
lying down and soundbites help, good idea. Do you have a video of last year? I once played it at 105% speed to really boost their self
esteem ("look how fast we are")!
But my worry would be not to do too many new things so close to the final, keep them in the flow....