UPDATE: Rather than soak the entire frame, I tied strips of shop towels around cable guides, stuffed them into crevices, and then soak with evapo-rust using an eye dropper. Reapplying liquid every few hours. Now, I need a sealer, but wonder if I'll be able to paint it on (rustoleum or Por15) rather than spray--the affected areas being so small. Anyone have any experience brushing sealer on? Is there also a lacquer primer you recommend? (Preferably white.) Rustoleum has some primers but I don't think they neutralize traces of rust like the Rust Reformer, which coats everything in black.

Color matching those top tube cable guides is going to require some experimentation. My local auto body shops said they can't help me. So i purchased a few nail polishes I think are close but may have to mix. I thought automotive touch up would be best, but the 2002 Thunderbird Blue touch up was disappointing in person. Fingers crossed.