by droopsnoot » Sun Aug 19, 2018 6:41 pm
There is an option code 507 for an Onyx (black) vinyl roof cover, if the SPI plate on the drivers side inner wing has '507' on it, then it suggests that it's a factory-fit option. Otherwise it might have been done by the supplying dealer, or maybe later on. I'd imagine that 40-odd years later, any factory-fit vinyl roof might be showing signs of age, and might have been replaced.
I did hear an "interesting" story - in the factory, part of the job of the final inspection team was to check the roof panel to see that it had no dents, and if it did, they would fix them by tapping them out from underneath and checking the paint wasn't damaged. If they still couldn't get the roof panel right, then they'd fill it and the customer would get a bonus free vinyl roof. Make of that what you will, and don't let it put you off the car.