My AC/heater vents never stayed in place. They always flopped around & rattled. I was planning to take this project on if/when I got around to installing a modern AC system. This probably won’t happen anytime soon.    I recently attacked the renewal of my gauge & glove box plastic surrounds. So it only made sense to address the vents now.    I was kinda excited that I figured out a fix on my own without thinking to look on the forum for direction & counldn’t wait