That begs the question: how does one find out the actual build date ? (I've never looked into that.)

But as far as order/build/deliver, it was probably all over the place.
In early 1989, a buddy & I ordered identical cars from different dealers that were about 40 miles apart in SoCal.
Mine showed up on the truck 10 days before his.
Both were built at the same midwest plant.
I would think production controls and logistics were better in '89 than in '70.