Welcome to the "mining club" so to speak. I have likewise been doing the same type of thing for several divisions I have been chasing down the many rabbit holes of chance.
In addition to The RR Telegrapher, try these: employee timetables, the 1912 full listing of stations, etc. for the entire system that I think Allen Stanley has on-line, and occasionally writers of the day who wrote their tales and referred to their stations often by their call letters, and I am sure there are a few others I can't recall at the moment. I have been chasing down the Washington and Danville divisions (only part of Danville) and like to think I have close to all. Occasionally you also have one here and there that changed its call letter or letters just to confuse the future historians like us.
My 2 cents worth.