Does anyone know of a resource online or elsewhere that describes (preferably with photos) the various characteristics of New Era caps that allow you to figure out when they were manufactured? New Era's site doesn't seem to provide much help, other than stating that the "Diamond Collection" caps started in 1986, the New Era flag logo was introduced in 1997, and the blue box logo was introduced in 2005. Particularly interested in trying to see how to distinguish between the various years in the '70s and '80s. Thanks