It's been a long wait, but here is a picture of Wiggles using this tube.
Wiggles enters the tube at the lower end and exits at the top. I was considering removing some of the rods to make it easier for him to get through. I had seen him using the tubes without rods. I'm glad I didn't. The whole point, really, was to give him a piece of furniture that requires him to move his body in a different way. Snake's bodies are designed to move through tight spaces. This piece allows him to do that. I'm, now, considering adding dowel rods to his hides so that he has to squeeze into those.