Here we see the standard Buick 6 cylinder engine installation in factory #06. This is either 1917 or 18. We do have a powered assembly line for the chassis.
This is the body being lowered from the second floor of factory #06 sometime probably in the teens. In this not to clear copy I made you can see some posters on the beam behind the car in which the heading is world Series but you cant make out which. As you see there is no moving assembly line for the final line yet.