Trip Meter and mileage dimly lit

[Tontastic]

The tripometer and mileage on my W210 1999 E300TD has suddenly gone dim (about half brightness), but the two items (date on one side, can't remember what is on the other!) displayed either side of these are fine. Any ideas?

 

[BlackC55]

I suspect a bulb has blown.

There is a "how to" on removing the cluster to do this.