Here is a picture of the bottom on one from a 67 SJ. You can see evidence of the galvanized finish. Not sure if the caulk-like material in the center is "normal". I have my suspicions due to what appears to be black paint which would not be original. They have since been cleaned up, and there is no part number stamp. One more thing - notice that the outer edges appear to be jagged. This is the case on all four after cleaning, the stamping process was not very crisp.
