I am not a restorer - the stuff I build I drive them all over, across country and back, and they are far far from perfect. I love patina and the way they came and look from long years of use and abuse. You see my avatar
Now you know where I am coming from, and if your car is driver quality or worse, whatever channel that’s left to hang the rubber on, I have used rust inhibitor on what’s left to stop further rust (it turns rust black), then get some color on them close to what is on the truck, and use weatherstrip adhesive to hold the rubber in place within the channel. It is by no means perfect but serviceable and for the most part, no one will ever notice unless you tell them. Lol!
That’s my story and I am sticking to it ..... I can feel the cries and of many Fordbarners right for now but if you are building it to drive it, you have a lot more things to get right than door weatherstrip. You can always fix it later after you get used to the used mig welder you just bought ready to conquer the mysteries that go along with using it ....