Early 1900's is the best I've found, it seems that record keeping wasn't so good back then. For your interest this man is actually playing one http://www.YouTube.com/watch?v=sG1ZUsnERV0
55001, 55002, 55003, 55004, 55005, 64995, 64996, 64997, 64998 and 64999.
As a 4-million city, the place is quite big. Zip codes range from 64102 to 64996.