I need to build an underground tram system.

[Scifi fan]

I don't mean 44 inches as in the guage; I mean 44 inches as in the length of the tram.

You need to read the responses more carefully. I said 44 inch cars and 7.5 inch gauge.

My apologies - I'm totally new. I am referring to 44 inch carriage, the sort that's pulled by the train. Miniatures of those sizes look pretty good on film.