I'm restoring a Stern Electronics Stampede pin, # 2544. I've noticed in the brochures that it mentions that there is a captive ball on the left side, leading up to the Horse Shoe. My machine doesn't have this. Is it a common practice to remove this feature sometimes? Do they wear out? Has anyone put this feature back in? The machine plays fine without it, except sometimes after hitting the Horse Shoe the ball will go straight down the center right between the flippers. I've seen pictures on the internet, some with, and some without.

Thanks for any insight.

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