Spent the day stripping off remaining paint, applying hammerite rust-remover, sanding with 1200 wet & dry and wirewool, and finally an autosol polish.
Polishing was probably unneccesary, as it'll no doubt be blasted before painting, but I wanted to see how shiny I could get the frame & forks.
I'm almost tempted to go for a clearcoat, but there are dark patches in the metal (discolouration rather than rust) which wouldn't allow me to do a perfect job. Paint I think:
All the external rust is removed, but I see some way down inside the seat-tube. Any reason to try and remove it? I can't see it being a problem during the painting process..