Re: 3 3/4 scale - track gauge?

To see a great example of 3 3/4" scale railroading, check out the Sandy Ridge & Clear Lake Railway site. This is a working 7.5" gauge railway based on the Maine two footers, although the cabs have been increased in height to accommodate full scale people!

Sandy Ridge website

The amazing thing about this line is the level of realism in the engine service facility. From the outside, it's a scale structure. Inside the tracks are raised on 3' high stands that allow full scale people to easily work on the equipment. There is a crew room and dispatcher's office also designed for full scale people inside!
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SR&CL Ry roundhouse

The owner is a retired Grand Trunk Western engineer and operates using time table and train orders. There are train order stations at several locations on the line where orders may be picked up and crews need to sign the register.

Michael Allen