Hmmm, I got around to pulling the dash apart this arvo to have a look at the globe that wasn't working. My old man told me we should have had some spare globes around in the garage, but sure enough I couldn't find the right ones.
Anyway, considering I couldn't be bothered going to the shops to get some, I decided that for now I would just swap the globes around so I could see my fuel gauge and lower half of the speedo at night, and not bother about the top half of the speedo for now. I never do much more than 110-115 on the freeway, so I don't need to be able to read that area between 120 and 180, but I DO need to know how fast I'm going around the 'burbs, and know how much fuel I've got.
So, having swapped the bulbs around, I checked my work before re-assembling the dash, and what do you know, the WHOLE area lights up! I checked that they were working at least four times again, during and after the assembly of the dash, and it's still all good. I know I removed, swapped and replaced globes, but I didn't actually change any...
Minor miracle of the day, maybe?