67 Cuda Fastback seals

Thanks again Redfish, I may have some more questions for you once my 68 windshield molding set gets here. Tony's Parts had a set and I should get it next week.

Now, i have a question about ther rear window...do you need the molding to use a 68 gasket? My body man says the way its designed that the gasket is more or less self locking. Is this right? ~Thanks!