If a color vision SODA was issued a few years ago for a second class medical certificate, can I present this same SODA for certification for a first class medical certificate? I was told by the FAA in 2001 that a SODA is good for all classes, but was told recently that might not be true. My AME has been issuing me a first class certificate with my current SODA indicating second class authorization. If I do need a new one, should I go through my AME or the FAA directly to request one? Will I need to do another light gun test as well? Thank you.