I took apart the 928 gauge cluster and used an electrolytic plate – the kind you use to clean silver – to knock the corrosion off the circuit board. It worked very well and the entire cluster is now brighter and more responsive than before.
To do that you have to remove every bulb from every holder and carefully unscrew/unbolt everything from the board. Then you carefully remove the black plastic connector tabs and slowly work your way around removing the circuit board. The tachometer part, the one with the three horizontal holes, is actually a plate with a few 1/2″ aluminum connectors in it, as I said, be careful removing this stuff. Pictures below…
If you don’t want to go through all this then you can clean some things up with a wire brush and patience. Remove every screw or nut, one at a time, and clean it, then replace it. Do the same with every bulb holder. The act of simply removing a bulb holder and bulb and then replacing them knocks off corrosion.
