The DIY paint job is flaking off in places, so I'm just hoping I can just scrape it away carefully and see what's underneath. If the original paintwork looks ok for the most part (there are places where the paint's been scuffed back to bare metal) then I might just give it a few coats of lacquer to preserve it. Apparently there should be some rather nice decals on the seat tube.
If it doesn't look good, then yeah, guess it's a take it back to bare metal, then prime and respray. I've no hope in hell of replicating the original two-tone finish, so will probably pick a sympathetic shade if that's the case. They made this particular model (Ranger) over a number of years, and prior to the fancier paint jobs, it came in either burgundy, dark green or navy blue.