However eventually the power supply will die. Mine would shut down sometimes and need to be turned off and then back on to get it working again. When it was working there was a dim area in the middle of the screen that was very obvious on white scenes. Then it smoked and gave up the ghost. The first thing you need to know is that you only need to remove one screw, the big one in the middle on the back side to remove the access cover. Then three small screws and the metal cover comes off. In the power supply there are two 10 uF 450 volt electrolytic capacitors. They sometimes die quietly and sometimes they will die with lots of smoke. In the picture below one of them is shown turned over so you can see the crud around the lead where the goo was oozing out. The circuit board was even damaged under the capacitor from all of the heat.
The best solution is to replace the capacitors with some non-electrolytic 'paper' types. I used some .47 uF at 400 volt capacitors. These capacitors are much more durable, they are used in Tesla coils because they can take a lot of abuse. If you look at the holes and the drawing on the board you will see that this was an option back when they designed the TV. The picture below shows the new caps soldered in place.
With the improvement the picture is back up and brighter than it had been. The dark area in the middle was caused by the lights being dim from the capacitors being bad. When the light bulbs are dim the light does not reach the center of the screen very well.