I have a 72 600 sedan and I am having a hard time finding the oil plug. Its not a normal plug because it looks like it has an oil pressure sensor type of rod going through it. I am going buggy trying to find someone to help out on figuring this out as well as looking for the part online. I am also not sure if I can just put in the normal plug because this is what all the part stores are saying that goes in their. I am starting the restoration process. Here is a picture of the item I have.
Did you ever find a solution? It looks like you could drop the bottom case and clean things up and place a bung right in the soldered in fitting.