At first I was thinking the M might mean marine but more likely it's for the Marysville engine plant.
I still believe the 9004 is the build date.
What is it with some of you people? Mr Kunkel you are at the head of the line, again. You have much good info, thanks for sharing. You don’t know it all, nobody does. So stop typing out your guesses and believe that others DO know something you do not.
I wasn’t asking if you thought I was right. I wasn’t guessing. I was telling you what these numbers mean. But hey, you never believed me on other items before, so here is your proof today. Notice how the build date doesn’t appear on the stamped pad until 1960 model year.
I would have posted this info before but I had to spend some time to find it again. I didn’t really think it would be necessary and this typed info would be doubted so much. Jim Lusk thanks for posting your 1961 413 info.
More info here.
http://www.chrysler300club.com/uniq/id/id.html
