GMAD_Van Nuys,
Interesting! I worked as a manufacturing/process engineer during 1985 - 1998 at the former Allison Gas Turbine (AGT) Division of GM in Indianapolis, IN. I was there when it was sold and eventually landed with Rolls-Royce Aerospace. I recall the Industrial Engineers under AGT also had labor standards; however, due to the low volume/high revenue per unit aerospace business, it was hard to hold production to strict standard labor hours. Some individual gas turbine parts took weeks to manufacture! Aerospace parts are very expensive, involve very specialize manufacturing processes, so rework is common an often done to salvage parts.
I left AGT/Rolls-Royce to help project manage and help launch two new Chrysler Transmission Plants in Kokomo, IN. These powertrain plants were very high volume (3200 and 1600 transmission per day), and operated under a completely different business model from aerospace. Labor standards were important but most all the fabrication lines were automated that used conveyors, pick-and-place units, robots, robotic vision, and palletized conveyors to transfer parts between operations. For the past 11 years I have work as a manufacturing project engineer at Allison Transmission in Indianapolis. We make a wide range of heavy duty automatic transmission for school buses, UPS/FedEx style trucks, ambulances, dump trucks, cement mixers, the tow trucks that push jets from the jet way, fire trucks, as well as off-road mining trucks and equipment. Allison also still make the transmissions for the M1 Abrams battle tanks!
All told, most all GM, Ford, Chrysler plants "back in the day" as well as today along with many other modern manufacturing plants, use work place organization and visual based controls for the operators to get the "status at a glance" condition of parts, part placement, quality indicators, etc.
When I read the book Echoes of Norwood Plant, aspects of Norwood reminded me of AGT! I can just imaging how challenging it must have been to implement a new computer system with printed broadcast sheets taped on cars for the workers to follow. I can just imaging that a portion of the workforce asked (revolted, complained, pushed management) for a simple sequence number to be marked on the body so they could quickly see and pull the correct parts for the car as it progress thru assembly. Some parts must have been marked with the corresponding sequence number, while other parts had broadcast sheet or some sort of sequence number sheet taped to them. The Echoes of Norwood book shows the taped sheet on the rear axle assemblies and front sub frame assemblies.