I've ordered replacement reproduction outer window felts twice now, and having driven the car in the rain today, I can tell you that they do NOT hold water. Given the design of the windows on a '72 Supreme, I'm tempted to just undercoat the inside of my doors and quarters and call it an aquamobile.

Anyone got a good source for window felts that actually work?

 

The repops brands felts work well in the front. The rears are a modify-to-fit deal.
Are your windows adjusted correctly?
None of them will actually seal out all water; just the majority of it. If the felt is contacting the glass, then it is okay.
The doors were designed to take in water, with bottom drains and the paper shield at the door panel.
I POR15ed my door and 1/4 interiors for extra protection.
If water is getting INTO the car, your shield is not installed properly (bottom end tucked in)

 

The windows are as good a fit as the new rubber allows them to be. Getting better all the time with use and weekly adjustments.

The fact that water was supposed to pass through the quarters and doors makes me feel better, then I just have to prevent those from rusting. I'll have to see if I can find the paper shields I never bothered reinstalling. :P DID wonder what those were there for.

 

Quick additional question: At about 75 MPH, my windows let go of the body-side rubbers and start letting air in. I assume they're not supposed to be doing that. What do you do to ensure they don't?

 

3m structual adhesive kit will hold if i understand you the rubber and chrome on the rear qter window possibly. Be forwarned though this kit costs quite a bit.