This is a very cool model (no pun intended)! A very nifty design, and paper models and card models are a neglected aspect of toy collecting. Excellent post.
It is great to see the card model actually built up like this. Sadly it never got made into a toy so the C21 card version is its day in the sun. There is a plastic model kit of the Snow Train in its shielded state by Imai, which is called the Beetle in the Project SWORD strips but the model kit is called Thunderbird 7. Have you got one Zigg?