Yep, very bad and dangerous idea!
No action should be undertaken via a restamp approach as it can't help but compromise the credibility of individual cars no matter how well intentioned.
If one wants to bring component date codes in line with a car production date, then seek out original unmolested parts and swap out the chunks that don't fit the accepted production time lines from back in the day. Alternatively, live with what you've got.
Once a restamp Pandora's Box is opened and accepted as credible, everything becomes suspect. Having said that, one cannot be naive in thinking it doesn't already happen at some level and freqency. Sad but probably true. My 2c.
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