I can't recall seeing any F&CC / MS equipment in Butte, and I frequently visited in the 1995 - 2005 period. There were several items of railroad equipment displayed at the World Museum of Mining on the west edge of Butte. The standard gauge Butte Anaconda & Pacific branch ran along the edge of the museum grounds, and the sole surviving box cab and tractor unit were on display with a single 50 ton ore car and caboose. All of this was moved to the Anselmo Mine yard before the rails were pulled up and the line became a hiking trail from Butte to Rocker. But I think all of the narrow gauge equipment at the museum was less than 36 inches.
CVM
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