You can actually find the dealer prep checklist for a lot of cars with Google, for example GM has theirs freely published on their public web site.
He's talking about fixing production errors, like panels being stuck on wrong[0], or window gaskets being misinstalled[3].
As a side note, this is the first time I've heard anyone defend the lemons coming out of Detroit in the 70s. It was so bad, that my dad would check the VINs, so that he would never buy a car that was built on a Monday or Friday, because it was too likely that the workers were either drunk or hungover.[1][2][4] And this is when he was in the UAW as mechanic and then a body man.
I thought these production issues might be overblown, so I checked the deck lids on three 3s in the parking lot at work. All three were misaligned. I didn't expect them to be perfect (it's not laser perfect on my 2010 Jetta either), but I didn't expect to fit my finger through the gaps. All three cars. All three in different places. That killed it for me. I will never buy a Tesla 3.
[0] https://teslamotorsclub.com/tmc/threads/body-panel-gap-and-a...
[1] https://jalopnik.com/the-ten-worst-car-factories-in-history-...
[2] https://jalopnik.com/5645880/auto-workers-drinking-getting-h...
[3] https://teslamotorsclub.com/tmc/threads/unfinished-metal-and...
I can see panel gaps being an issue for some cars, but I can't see the deck lid being misaligned to the point where you're able to put your hand through any gaps.
A photo of my hand can be provided upon request.
EDIT: whoops, missed the context. The above just tells you the model year. But you were replying to someone that implied it could be done down to the day. It can be done down to the month, but in my experience down to the day is rare, if non-existent (none of my vehicle VINs have that resolution).
I’m telling you what I remember him telling me. How accurate he actually was, I don’t know. But Detroit earned their horrible reputation, and the Japanese manufactures are them alive.
Is that the "dealer prep" line that always seems to appear as a non-optional line item in the price of a new car?