Vinyl Top car rear window weatherstrip question

If I'm understanding you correctly, you're not replacing the vinyl top and it's a hardtop car, yes?

If that's the case, the rear seal for a hardtop will be your choice. The difference between the two gaskets is that the vinyl top gasket was different to accomodate the vinyl.

I have a 71' Dart Swinger that originally had the vinyl top which is no longer The case and when I replaced the rear gasket, I went with the hardtop gasket and it fit with no issues. I hope that this answers your question.