I generated another Ridgway overlay with the less detailed milepost 0 sheet which was in better condition than the Ridgway station map. I also tried to pull the overlay a little further south since there was some concern about the street alignment. Even so the center of the turntable on the overlay is still going to land in the center of Hyde street. I also placed a yellow marker at what I think is the center of the circle that is evident south of Hyde street. As you can see there is very good alignment along the longitudinal axis of the center of the turntable and the center of the circle on the ground. Along the latitudinal axis I calculated 42.6' between the centers of the two items using a lat/long distance calculator. Fairly close to the turntable diameter of 50'!
Center of the turntable on the overlay: 38.150417, -107.755431
Center of the circle on the ground: 38.150296, -107.755433
Dave