I just bought a 1990 340 1.4 for pennies, and in my favorite colour

It came with a few problems, and before I start debugging them one by one, I was wondering if some could be related (common fault).
- Speedometer doesn't work
- rev counter doesn't work
- economy-meter-thinguie doesn't work
- medium lights (don't know how to say it in english, the lights that you use while driving at night.. not the high beams i think) don't work
- oil (?) temperature gauge doesn't work ( http://i.imgur.com/afWHvWY.jpg this one )
Now before I assume the previous owner changed the dash and didn't connect all the stuff, here is what works in the dashboard :
- backlights work
- presence light indicator (little green lamp) works
- fuel gauge works
- water temp gauge works
...
and the high beams work when i pull the lever to "flash" them, but they don't stay on.
I've checked the fuses and visually they look ok.
Any clues on this?
Anyway, grats on a great forum which i've been lurking for a bit now, and heres the old thing :
