Comment and a question: A common paint shop practice is to disconnect the battery while painting because of static electricity. In so doing, it may have resulted in a bad ground anywhere due to the surge. When it comes to ground issues, it is not a sure thing to assume the closest or related ground issue is the culprit. I once installed a towing light assembly on my S-10 and that started a problem with my turn signals, emergency flashes, etc. I had to do all kinds of checking and spark chasing before I realized it was the ground at the back of my truck that was causing the problem.
You stated you replaced the printed circuit board 5 years ago. If you installed a new circuit board, then your assumption and belief that it is okay may be correct. However, if you replaced the circuit board with a used one, then that may be your culprit as well because those old circuit boards get so darn fragile as they age. The copper tracings can break under the protective coating and are generally not visible without step by step continuity checks along the path.
Now for my question: How did/or do you remove the metal U-shaped clips which serve as the connectors for the gauge cluster? I am preparing to switch from idiot lights to gauges and am trying to remove the clips without demolishing the printed circuits. As a backup plan, I am considering soldering and running wires in lieu of relying on the printed circuit.
Good luck as you try to locate the problem and let us know what you find.
