Considering the butyl ribbon was used originally,I wonder what roll-over standards were in place in say 1970 ??? ...Anyhow...The original factory butyl strip had some type of cloth backer facing the interior side of the glass so it would'nt stick to the interior parts when installed...I've never come across any of that stuff for sale...Just as others have said...Use the primer on the car's channel, install the butyl strip {in a warm enviroment}...Then use the urethane around the channel to seal the deal...You need to fill the channel so water does'nt lay under the trim...Or you'll have spots like the back lower window channel rotting out just like they did originally...