Chevelle Trim Tag?

[David C.]

I have been asked to paint a 70 Chevelle convertible big block car with an unusual trim tag. Has anyone ever seen this date before? The owners told me the heads and block were cast in september (I may be wrong, but think that's what they said). Motor is numbers matching, owner did not even know there was a vin on block, luckily it matched and trim tag has never been removed.