1967 vs 1968 windshield trim

There are 2 different types of 68 up gaskets. One is a one piece self locking design and the other is two piece requiring a round solid rubber lock cord.
Yeah they get confusing. A 2 piece gasket is much more flexable and easier to R&R so it is prefered in trucks where the glass is more often broken in the field. It was also prefered on the assembly line where a new opening, glass, and gasket are going together. Thus another reason for the 2 piece gaskets in first year of second generation A-body.
Be sure to clarify 2 door hardtop or 2 door / 4 door sedan. They aren't the same.