I have seen a few very early 1971 models that had 1970 clear parking light lens and 1970 rear tail lights. My understanding that GM were using up 1970 Nova parts and they had a strike when they were building 1971 Novas. I even saw a 12 Bolt in an original early built Nova SS 350. 1971 was a oddball year and the 396 was gone for good in Novas. I also saw a early built 1971 Nova with a big block heater core box.
