The best headchoppers are on the GEMINI, but I have looked closely and they have about 20 foot clearence. The two tunnels on MF are exetremly wide, maybe fifteen feet wide, and 20 foot high.
They are not really head choppers in my opinion because they are not even close to the track, and you can see them coming. The camera is in the second tunnel. The tunnels on MAGNUM are 9-10 feet wide and 8-9 foot high. Also, you can see them comming, and they used to have stobes, and
fog. Not all tunnels are for headchopping.
ZEPPELIN RULES