Actually, your whole point was that the rest of us are dumbasses.
"We" don't think deception is okay. "We" just realise that these cars are 40-50 years old and that it's unrealistic to expect them to have the same OEM Westinghouse headlamps installed after all these years. Originality is all just a matter of degrees.
Graveyard Carz will replace every single panel on that phantom Cuda, but it won't be a "rebody" because it'll retain the OEM firewall!!