According to the 6066GMCGuy
http://www.6066gmcguy.org/VinNumber.htm , they built GMC trucks in the Fremont Assembly Plant in 1966 … therefore Chevrolets and GMCs were built in the same plant. Does anyone know if they were mixed together on the same line? I can see how they would basically build the same, but there were so many minor differences they may have had separate lines, maybe separate parts of the plant. I don’t know why this never occurred to me before.
I think the Pontiac West plant built both Chevrolet and GMC medium duty trucks as well as GMC light duty trucks. Are there other plants that were
integrated ?