I think I have decided to try and go the touch-up route with my Tempo I am stripping down and rebuilding this winter. The paint is in so-so condition. Much of it is nice, but with lots of chips here and there. The brake cable eyelets across the top tube are bleeding rust on the white paint too. I'll try the nail polish route first, but just curious if there are any tricks. Do I need to sand the area first? What about spots that rust is starting to develop, like the eyelets. Any kind of primer down first? And assuming it turns out well, should I try and do something like a clear coat over the whole frame again to protect whats still in nice shape from damage?

You might search the forums. There was a discussion of using a weak Oxalic acid solution or rust removal gel to clean down to bare metal without marring the paint.

There's also this list of rust removal products.

I plan to follow this project with interest, because I am now motivated to get the Capo Sieger spruced up and back on the road. I think I can salvage most of the paint job, other than the head tube's red enamel, which was coming off in big flakes, so I'll redo that.

yes, lots of info in the forums already. I am slowly gathering some links to threads on restoration topics in hopes of making it a sticky. In the meantime, here is what I have that's related to this:

Paint & Finish:
To paint or not to paint: TO PAINT OR NOT TO PAINT?
Rust - https://www.bikeforums.net/classic-vi...-anything.html

Lots of people have mentioned blending Testors and or Tamiya model paint to get a near exact match to the existing paint color. Here's a link to a search for Testors: https://www.bikeforums.net/search.php?searchid=12250696 I also remember someone talking about using a sander that is essentially a bit of sandpaper at the end of a blunt tipped holder. They would use that to taper the edges of the chips to smooth things out. Maybe someone can refresh my memory.

Not sure if anyone has recommended one of these fiberglass scratch brushes yet. Works great for cleaning a small spot down to the metal and then touching it up with paint. Much more precise than sandpaper. Tradeoff is not very good at feathered edging which I've never quite gotten down in my touch up technique.

Amazon.com: Scratch Brush, Fiberglass (Colors may vary): Home Improvement

I recently rebuilt a beat up Raleigh Portage mtb that I decided to leave stock. Fortunately the paint was black and easy to match so I masked off the decals and chrome and lightly over sprayed it and then top coated everything with lacquer. It looked pretty decent; just a little better preserved patina instead of sparkling new.

Unfortunately someone stole it from my front doorway. I hope they appreciate those little touches...