Building a working interlocking

[TrainWatcher]

I read Don Ball's article in the January and February issues of MR about how he built a working interlocking machine for his 1895 era road. After reading the original MR 1961 plans (links available in the link provided) I have begun to think about reproducing a few "machines" and working to re-create some of the local interlocking plants such as Delray or BO as a great teaching tool to be used at various local train shows in a modular format. My question though, is where can one find tower dimensions for a place like Delray publicly? As I am unsure the railroad would be willing to share the building plans of a current working interlocker.

http://mrr.trains.com/how-to/tips-proje ... cle-series

[Saturnalia]

Could screencap the satellite imagery and scale it up. Not that difficult.

[SousaKerry]

There was a guy I knew in Tiffin, Oh who was an O scaller and belonged to the COOSE? modular group out of Columbus. He was an electrical Engineer and used an old PLC and HMI to build his own interlocking(electronically) to control a double crossover on his modular sections. It was overkill to the extreme but it was cool.

HMI = Human Machine Interface (touch screen)
PLC = Programmable Logic Controller (Used to computer control industrial machinery)