That could be a tough one. The 42nd, Rainbow, Division was formed with men from all 48 states. If there was a National Guardunit from around Plattsburg that was in the 42ndyou would be on to something. But, beyond that, your option would be to persue the records of the person you are familiar with. His dicharge papers may have been recorded by his county recorder to guarantee the records would always be available. A talk with any historical society that is around Plattsburg may also be helpful.