Bandit asked me for some stories about my Coop work at GM in '78 and '79. Here's, a couple of quick ones. At that time it was a straightforward manufacturing plant. Pretty straightforward stuff.
My Industrial Engineering supervisor was as I recall Dan Cameron, who was 40 or so at the time. He had a Sunbeam Tiger and was very involved in the Tiger club. He was a real car guy and top notch engineer. I really liked him. I tried searching for him on the web but no luck.
There was another supervisor that had a '79 Vette 454 that he bought through the factory plan. Everybody bought a new car every year and had a 13 month balloon loan so they had to sell it as there was a new one coming. I thought at the time it might be a deal. I guess it was one of the worst vettes ever. https://www.edmunds.com/car-reviews/features/top-10-worst-corvettes-of-all-time.html
I remember one time walking with another supervisor through the plant and he said boy, "this plant must be behind in production". I asked him how he knew and he said look at all the inventory at the manufacturing stations. He said they did that so that whatever happened they wouldn't have a shortage of raw materials.
He explained to me that a factory is like a beast of nature. He told me "there is no beast in nature with an alligator's mouth and a tweety bird's ass" If you stuff enough stuff in one end, something has to come out the other. He also said the fastest way to be an ex-GM plant manager is to shut down Willow Run due to lack of parts.
Another story was '78 was the last year of the big FWD Eldorado. And they got a lot more orders than expected. Saginaw made the tripot front wheel drive axles. The supplier had built to forecast and the tooling had been pulled so now they had orders but no way to build the tripot CV joints.

I found out because one day I walked by a corner of the plant and there were a bunch of guys with a pile of reject CV forgings that were supposed to be returned to the supplier and scrapped. They had micrometers and were measuring the surface that plugged into the transmission seals. I believe the problem was they were not concentric and they were looking for rejects that were good enough to build axles with. I bet a bunch of those last run Eldorado's had leaky transmissions. Well, you know the saying about plant managers and Willow Run.
One last story for the night. The plant made the GM emission Air pumps and they had a chronic problem was that some would show up at the assembly plant locked up. They found that out after the car was built when they started up the engine on the line for the first time and the pump is locked up and won't turn and the belts are screaming. I recall being told that they cars were pulled off of line and sent to a rework department to be repaired. It was a big department.
Now each pump was dyno tested after assembly so they were turning when they left the test station but maybe something loose internally and locked it up. So I was asked to look into it. One last thing was that the pump had a filter fan (a plastic fan on the front of the pump that made it hard for dirt to enter the pump).

The plastic fan was on the front of the pump and as a part of the packing, the guy on the line would pick up each pump and give the fan a twist to see if it was free. I walked by the station several times a day, and the guys were always doing it. I did not believe that they were letting bad pumps through, so what was the problem?
Well I looked into the fans which were also molded in the Saginaw plant and they were made on three different 8 head/station molding machines. Well guess what, nobody really was following the ID dimensions of the fans because as long as the hole was big enough that the fan pressed went on the shaft everybody was happy. And that was the problem, one of the stations made fans whore ID's were really too big which resulted in a loose fit. Not a problem as long as the pump worked because the fan was pinned by the pulley. But this was a problem as the guy packing the pumps could not tell when he grabbed the fan to spin it whether it was the pump turning or was it the fan spinning with the palm of your hand when he gave it a twist.
Well that was it, they tightened up the tolerance by rejecting the bad fans and they could find the bad pumps.
Anyway I walked into Dan's office and told him how I had figured it out and there was the department supervisor there. Well afterwards the supervisor told me that in no uncertain terms I was not to go to a manager above his head without talking to him first. He was pissed. Lesson learned.
I did my second summer and was one quarter from graduating from Iowa State. I considered my options and decided I did not want to work in manufacturing Industrial Engineering. The reason was if you were really good, maybe you got to run one quarter of the plant. Not my cup of tea. I ended up in new product development/marketing in the air conditioning industry which much better fit my interests.
Nuff for now.
bob