What about doing something like this 'circle tour' using buses, combined w/American Oriental Express trips?
Those are big-buck trips, and fairly lengthy, but they already go thru parts of Colorado. Perhaps those trips could be enhanced w/stops to tour the CRRM, C&TS, D&S, Ridgway museum, Ophir area, etc.
They could get near enough to Ridgway (via a stop at Grand Jct) and Golden w/o much trouble, and perhaps bus trips down to Ophir, Durango and Chama would also be possible. Then there's the Gerogetown loop, abandoned mines near Leadville, Alpine tunnel, etc. Shoot, I'd take such a trip if I could afford it!
This brings up another point - perhaps a 'RR chamber of commerce' is needed to promote and market things like this, a chamber made of marketing reps from all of Colorado's tourist lines.
Whadda ya think?