The first 10 cars [with show on trim tag]were often pulled off the line to get a better fit or finish. Cars with "issues" fell into the same category The first car off the assembly line did not mean VIN #1 , the Pontiac "experts" should know better than that.
The first 10 cars off the line were not necessarily all SHOW1 cars..in fact, it is well documented that Show1 cars were dispearsed throughout the run.
Do you have documentation that the first 10 Firebirds were in fact Show1 trimmed cars? Or are you being "general"? The same question goes for VIN 1-10 as they came off of the line.
There is no specific documentation that I have seen, know of, personally talked to people "in the know" and have spoke to people who have worked on the assembly line. No documentation that I know of exists.
As well, SHOW1 on the trim tag SPECIFICALLY meant (and for no other reason) was for hand picked parts, better fit, finish specifically for auto shows.
Just making sure supposition and conjecture isn't clouding fact.
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1967 Starlight black PMD Engineering 400 Auto 1968 Alpine Blue 400 4 speed 1968 Verdoro Green 400 HO 4 speed 2013 1LE 2SS/RS Inferno Orange Camaro.