Topic: application for trunk weatherstrip C5ZZ-6343720-B?

[21.04]

I've got a mid to late 70's Ford replacement trunk w/s for a f/b that is in a brown paper envelope with a Ford logo on the front.  As I search through past threads here to determine the correct application, I am not certain I've found the answer.  Hoping someone can tell me what I have.  Although it as a C5ZZ number, the core is a trapezoid design, rather than a C-shaped design.  Many who have contributed to past threads on the subject of f/b weather stripping have indicated original style w/s for '65-66 f/b should be the C-shaped design, and possibly the trapezoid design originally installed on '67-68 f/b.  I'm interested to hear what others know on this?