On this page I list some references I have found for prototype research and modeling ideas.

"The History of North American Rail", by Christopher Chant, ISBN 0785814558, published by Chartwell Books, Inc. in 2002. On page 273 is a photo of tourist attraction of a replica 1800's steam locomotive on a turntable. About half of the turntable is visible. It is in good condition and could help in modeling the bridge boards and safety railings. Page 294 of that same book shows a low-angle shot of a turntable at the Bangor depot in Maine. This is a working version and clearly shows the bridge structure over the center of the bridge.