Here you go. (white lines are 2' contours.)
Since I'm sure someone will question it, the "Coal Bin" out by the garage is for truck delivery purposes. A smaller coal pile is planned somewhere behind the roundhouse (along with a proper ash pit.)
Also the blue bumpout on the Car Barn Exhibit hall is a proposed concept only. If built, it is intended for storage and display of smaller motor cars and the SR&RL Railbus.
The current gully/drain between the roundhouse run-through track and the roundhouse lead track will be filled with a basin installed, etc. This also allows the run-around track to sneak by the East side of the roundhouse.