Thanks Richard.Bob,
Let me confirm, but I was thinking it was the same screw as used for the wheel lip trim which is the 672 screw.
Wow. Excellent pics and description.Bob, these were on my car for the last 33 years and probably since new. The head diameter is 5/16", threads are 7/16". Looks to be #6. The top of the panhead has a very small triangle stamping.
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