Finally, I applied lithium grease to the length of the metal rails, wherever the nylon part of the window carrier tracked. You can see the far right tracks on an inverted T-rail. I cleaned the old stuff off first.
Yeah, like this. I'll just say that it took me eight months to do the research and screw up the courage to tackle the project, but I am glad to have a working window now.Eesh. At the rate this is going I almost wish I could just convert to manual windows.