I recently purchased a 12 ga. Simson (made for Ivers Johnson). It's a cute little gun and I'm looking forward to chasing woodcock and partridge with it next fall. In the meantime I would like to learn a little more about it. Is there a way to identify the year and model from the serial number? The number on it is 25669. Since I'm brand new to the world of Simsons, any information is helpful. Have any reference books been written for Simsons?