I have an Apple 23" HD Cinema display. The upper half of the screen is dim and flickers. I have tested the backlight inverter and it is ok. It appears to be the upper backlight tube. Has anyone replaced the backlight tubes successfully? It seems that moniserv.com sells the tubes and claims it is an easy replace. Any ideas? Thanks.

UPDATE: The ccfl tubes arrived from lcdpart.com. Taking apart the monitor I found a cold solder joint had broken on one of the upper tubes. This monitor has six (6) tubes not four. Replaced the three upper tubes. They are very small in diamter and the wiring is tiny. With care it was possible. The tubes, as advertised were an exact fit. Puting everthing back together I was rewarded with a working montor. It is fiddly, but, with care, it can be done at home.