Last of the "COPO" style cars?

[salt27]

What does "COPO" mean?

"Central Office Purchase Order"

I always thought the P was for production.
as always, could be wrong.

I think you are correct on (production).

Also I was under the impression that they rated the 69 ZL1 at 430HP same as the L88 and the it was the L71 that was rated at 435HP.

Understand that I was not very old in 69 and I could be wrong,  Don

[Duramax]

Doh and DOH! 

It would have to be Production Order.  Purchase Order means they are buying something.  That's probably why my wife does the books.

And it could be 430HP.  I was pretty sure it was just slightly over 425HP.