Need help understanding date codes and sequence motor numbers

Alaskan_TA,

Thank you for that info. Very enlightening to say the least. Then the next question I have is you could have a engine date cast into the side of the block in my sequence case June30, 1971 and the transmission date cast of August 15,1971 but both and the car’s stamped showing my build sequence number.

So when these tv car shows are showing an “all original and numbers matching” they can only go by the sequence number and only know that the casting date is before the car’s build date, so “it’s possible” it’s all original. I try to sit thru an episode of GYCs and it seems as if Michael Scott wanna a be has a full production schedule memorized. But in reality it is just making sure date codes and sequence codes “jive.”

Thanks for the help
The mud is a little clearer now.
Joe