Guys, I'm trying to settle a disagreement. What years were the magnum 440's built? I am figuring 67 to 71 is about right. Have a guy with a 1980 motor home with a 440. I have seen other motor homes with 440's built and registered as late as 80 or 81. This guy is convinced that he has a magnum just because it's a 440 and I'm trying to prove that is not the case. Chevy guys should not reproduce.