jvd69z, There had to be some level of coordination between Fisher Body and Chevrolet final assembly. The bodies from the firewall back were near complete before they “went thru the wall” to Chevrolet assembly.
On example of coordination was the batches of the final color paint that were slit between the two plants to maintain color match when the entire front sheet metal dog house (painted on the Chevrolet side), was attached to the body and powertrain that was painted by the the Fisher Body side.
Using my LeMans Blue X33 (RS) Z28 with factory installed (and date coded) ZL2 hood, we have to assume that the two plants sequenced and coordinated the two portions of this LeMans blue Camaro to come together at the appropriate time. The body firewall was punched for the 4-speed speedometer hole, the holes for the RS hose grommet and ZL2 hood wiring grommet, etc. If I recall correctly from the report covering the Norwood assembly process, there was a broadcast sheet attached to the Fisher Body, and a 2nd broadcast sheet that applied to the car by Chevrolet final assembly.
Many years ago at a Camaro Nationals, I saw a very well restored ‘69 SS with a sequence number written on the firewall (by Fisher Body), and the same sequence number applied to the spare tire rim, and also on the inside lower front valance panel. That lead me to my most recent question, to get feedback and understand to what extent the sequence number was applied to Norwood build Camaros. How did they match up my LeMans blue prepares RS front fenders with my LeMans blue prepared body?