Not sure what vinyl Porsche used in the 70s, but Toyota and Datsun had some pretty thick stuff. The vinyl on American cars was prone to cracking. Pulling a door panel off a 1 year old Pontiac would lead to tearing the heck out of the stuff. And all of the cracked dash panels, ugh. I guess it was the mid 90s before vinyl technology got better.
I’m just rambling now.