Our new hire class was the last class to be trained on the DC6/7 as Co-pilot/Flight Engineer. Those were the last days of seat swapping (FO/FE). When the 6's were retired (about 7 months later) we all moved up to copilot in various aircraft depending on where you were based. I went to the BAC111, others to the L-188, some to the 727, etc. Our DC6/7 FE rating just faded away. The 6 was fun, low & slow where everyone looked out the windows to watch the towns slide by. American only had 1 DC7 left (freighter) and I heard some interesting stories about those cantankerous but powerful engines. That rapidly fading era was a memory never to be forgotten.