My Bird is #200 on the NASCAR list.

I would agree with the above rationale. But even today in some rare instances, parts on the assembly line can be substituted if they don't affect safety or government compliance restrictions just to meet production schedules/quotas. I would think 40+ years ago when things were simpler and less rigid, it happened more often.

Let's face it, trim rings aren't that big of a deal in the grand scheme of automobile production - not like transmissions, engines, etc.