I installed new run channel kits on my 48. Passenger side works real good but my driver side is tight and rolling the window up and down is very difficult. I actually broke the crank on my regulator. I played with the guide that bolts inside door and checked it out. I made sure it was straight and reinstalled. I can tell it is still a bit tight bc moving the window up and down when not connected to any thing is still a bit tight.
Kind of gave up in disgust and figured I would reach out to some fellow bolters...
Frank 1948 5 Window Chevy 3100 an absolute rescue that is now back on the road 1953 Buick Super 1 family owned since new
You need to follow the directions in the Factory Manual. Roughly translated, you loosen the regulator screws, then snug them up so the will still move once the window is rolled up all the way, then tighten the screws. This lines up the glass to the channels. Carl Feeling your pane. (Pane. Get it? Sorry, I've been reading a book full of Far Side comics.)