67 Barracuda trim?????

Just want to point out, you have to remove the glass and replace the gasket in order to drill and install the clips for the stainless trim, so factor that into the cost & time. But my car is in the shop for paint, and the stainless is absolutely on the agenda -- that plastic crap won't last a year on a car that sees the sun regularly. It might be OK for a museum piece -- you'd only have to replace it every 5 years.

Beware... the 67 body will have slight imperfections where its panels are put together. These wouldn't show until a nice straight piece of reveal molding is placed beside them.
In 67 the factory workers didn't get them perfect because they didn't need to. 68 workers had templates to work to. This includes the length of the fence that the gasket sits on.
You'll want to check and trim that fence as needed, especially at rear glass. If that fence is too long for the 68 up gasket you'll have a hard time getting the top of the gasket to roll in against the headliner properly.