Thanks for posting the plant worker's reply. It is very interesting. Maybe you will hear from someone who worked for Cares and Concepts (C and C) and get some information on the conversion process from their point of view.
When I bought my convertible in 2007, I thought I was buying a factory-built car that had been designed as a convertible. They still look pretty good for a conversion convertible, but from what ManicMechanic reported, there is a lot of sloppy work hidden under the trim pieces. And if Oldsmobile was losing $10,000 on every convertible, you have to wonder how much pressure C and C was under to convert the cars as fast as possible for the least amount of effort. That might account for what ManicMechanic saw.
Thanks again for sharing the worker's recollections. Sounds like the conversion was anything but streamlined.