Based on the 1919 service area of a New York Central yard called McKinley Avenue (also West Columbus Yard) in Columbus, Ohio:
http://www.columbusrailroads.com/new/live/05Steam_Railroads/13New_York_Central/13West%20Columbus%20Roundhouse/west%20cbls%20roundhouse.pdf

This plan copies the real one, compressed and reversed. This will likely be halved - from two inbound / two outbound service tracks to one each.