There is an outfit called RTech Fabrications,
https://www.rtechfabrications.com/ that does something similar.
In Pavillions in 2017 I saw one of his builds - good god you swore it was GM factory it looks so good. Craftsmanship over the top, body integrations were seamless, lines tight too, paint perfect, and modern everything... chassis, suspension, drivetrain, interior. If money were no object, I would absolutely own one.