firewall markings

[Bob Jenkins]

I have a 1969 Camaro SS 396/375 and began restoring under the hood. On the firewall above the heater core/blower housing I found the number 179 written with marker which was not affected by the cleaning. This must be the daily job number for the body sequence that day? Then as I cleaned the rest of the firewall, right near the center to the left of the wiper motor is the marking CoPo also hand written in marker?
Just like that Capital/lower/Capital/lower.
My car is not a COPO car.
This is very clearly written, is it a mistake? I have been taking pictures along the way just for my own documentation. I just thought this was interesting to find.
I know most early '69 COPO cars were built
the 2nd week of January....


Here is my trim tag and vin info:

VIN: N577451


TRIM TAG:

ST69 12437 NOR 219570 BDY
TR 721 57 S PNT
01B X22