Hi Don,
As you are discovering there are not nearly as many pictures of Chalk Creek and even fewer people who try to model Chalk Creek.
There are several pictures of the turntable in various books. In Tom Klinger's South Park's Gunnison Division Memories on page 147 there are 2 photos after abandonment. In Don Helmer's Historic Alpine Tunnel on page 121 there is a very small photo that shows the complete turntable and pit. Attached is a Jackson Thode photo that shows the lattice under the deck. A second photo from the Speas' family collection, provided by Margaret Coel, Sam Speas' grandaughter, shows engine 67 on the ground and the down hill side of the turntable pit. Lastly, there are 2 photos of the turntable on my railroad at the west end of Romley and the end of my railroad.
On another matter - the 1918 valuation map only shows one track crossing the metal bridge at Pomeroy Gulch. The map shows what probably is the trestle on the east side of the bridge. The photo of Neal Miller's car on the bridge clearly shows the top of the trestle bents.
Hope this helps your project.