Is there any kits to rebuild the door or window operations so that they work more smoothly? I have a 1967 289 coupe. I heard that they used leather washers and that if you replace things like that it work more smoothly

 

would it be better to just replace the worn out pieces?

 

If I were restoring, I'd replace the regulators and all other crank parts. Go to places like this to get your parts. http://www.kentuckymustang.com/frames.htm

 

I replaced the window regulators in my 68. I used to have to lift up on the windows while turning the crank and now they raise and lower easily. I also replaced the cranks because the little teeth were pretty chewed up. I cleaned the old lubricant off the slide and replaced it with plenty of new. There isn't any leather, at least on the 68.