Just like my obsession with the freight station that started me down the path of modeling the Pacific Electric in N Scale, the Pacific Electric interlocking towers got stuck in my mind.
Unfortunately, there isn’t a kit in N Scale that matches the prototype.
Fortunately, there are plans for a basic interlocking tower, just move some windows and doors around.. http://www.trainboard.com/highball/index.php?threads/interlocking-tower.87092/#post-945884
I built this using Evergreen 0.020″ V Grove siding with 0.040″ spacing, Grandt line windows and doors, Plastastruct stairs and handrails, and finally the roof of a Micro Trains box factory.
This tower is a generic tower and has parts from many that existed.