The tag on the door will give the month/year of production, but not the
day, if they want specifics. This same tag has been placed on GM cars for years and years...it's even still readable on most of them!
I can read the tag on my '74 easily, but the tag on the '85 is deteriorated enough that it's a little hard to read, as are that tags on both of the Cadillacs. They just don't make 'em like they used to...
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1974 Coupe, Multiple NCRS 'Top Flight' 1985 Coupe

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