The search has been exhausted on finding the serial number on the Airstream. I have searched high and low, in and out. I can see where at one time there had been a metal plate by the door but I cannot for the life of me find anyplace that the information may be hiding. The question I have is what happens if I cannot find the serial number. My understanding is that I need this infomation if I ever decide to join any of the Airstream groups.