Pinocchio inspiration

I was thinking about my animation adventure. I want to make this quite an atmospheric adventure that will make the viewer really use their imagination, so I thought of how I loved the part when Pinocchio goes into the whale's mouth in the Disney version of Pinocchio. I re-visited the film to see how they created the vision of being inside a whale, clearly this is fantasy, but how to make the viewer realise where the character has gone?  I think the key elements are the teeth on entry and the rib-cage inside, hopefully with some squidgy textures.