Everything else is working/ lighting up. What I have noticed is if I turn on the lights during daylight the dimmer does not work. It only works when it starts to get dark. That would indicate that there is a sensor somewhere but as everthing else lights up even in daylight, it cannot be affecting the cluster illumination.
I'll check fuses are in correct location. As the cluster had some illumination before I removed it to change the broken bulbs, I think it is something else such as poor contact of the pins in the plugs.
There are really only 4 bulbs that illuminate the dials, all the other stuff like time clock, mileage, temperature have there own bulbs, is it the case that all illuminations are out or just the dials?
Below is an earlier cluster but quite a similar layout to the later type.