Remember, "polish" means a substance which is at least mildly abrasive. "Wax" will coat the finish, but will not remove scratches.
I like 3-M Finesse-It II machine polish for things like this. It works best with a buffer, but enough elbow grease will also get it done.
There may be a Meguiar's product which doesn't come with a recommendation for a buffer - probably because it's a more aggressive cutting formulation. I'm sure someone will have a specific recommendation.