When I worked at the factory the visors were a subassembly job done by one person per shift and the guy who did the job on the night shift I was on was a buddy of mine, used to do lunch and sometimes brakes together. On occasion I would watch him make them, no there was no difference between one side of the other. it was that way company wide for all of the GM plants, as I worked at GM assembly plant in Framingham, MA and Saturn. just simpler I guess.
Technology is great when it works,
and one big pain in the ass when it doesn't
Detroit iron rules all the rest are just toys.