I am looking for background information about a semaphore signal blade I recently inherited from my father who was ex-PRR/PC/CR. He was working on the PC's Detroit Division circa 1972-74 when he brought home this piece of railroad equipment. I was in high school at the time but too many beers and loud noises (Iraq & Afghanistan) in the meantime have contributed to me forgetting what he told me about the origin of the semaphore.
What I vaguely remember is him saying there was an interlocking modernization project somewhere in the Detroit area on a former PC track. It could have been West Detroit or something called 'Townline" perhaps. Not sure which and now that Dad is in the big railyard in the sky there is no going back to him for the answer.
Anyway, if anyone is familiar with a project to take down semaphores in the Detroit area probably in the summer of 1974, I'd like to know what you know. For the curious, this blade has a squared off end and is a faded red with white stripe. There are three intact lenses, green, yellow, and red. The casting that holds the lenses has a big E embossed in the metal.
Thanks for any and all replies!