47-55.1 Walking visor?

[Livemeyer]

Just installed new cardboard headliner and new driver's side visor (with the chrome arm). I was a little disappointed after mounting to find the arm doesn't go straight across, it sort of sags, or angles down toward the middle of the cab. What's worse is that when driving, the whole thing doesn't stay against, or even near, the windshield. In a matter of a minute or two I find it touching my forehead and I have to push it back toward the windshield. Is there a way to prevent this "walk?" Modern vehicles have a clip the end of the visor squeezes into. Unless I'm mistaken, these old trucks didn't have that available.