Classic speedo needle illumination

The speedo needle on my 3.5 classic isnt illuminated. I presume that there is a bulb in the speedo that shines down the needle (like the tacho) but I cant see anything??

'Oh deep joy!! I've done this bloody job 3 times over the last 4 RRC's. Having removed the entire instrument panel housing & stripped it down to access the front of the speedo, you'll find that all that has happened is that the fibre optic has come out of the needle. My tip is to replace it with just a dab of clear silicone on the end & leave it for half an hour before re-assembly otherwise the problem will re-occur. Two minute job to fix, but over an hour (the first time at least) to access the bugger & replace everything afterwards!