normally the pins that fry are the big red one from the battery and the 12 ga black one from the alternator to the ammeter as the spade terminals used aren't large enough to handle the higher amperage of these circuits...add the extra resistance of some corrosion into the mix and you get a meltdown...pull the connectors out of those locations and run a new wire straight through the plug , crimp, solder and shrink wrap to a good spot on the original harness...other spots may just be easier to replace the connectors than to try to clean them depending how bad they are...American Autowire makes a non-insulated terminal crimper that's expensive but actually works, unlike the 3 different look alike Amazon ones that I sent back and the Channellock one that I'm stuck with...Deoxit is the stuff you're thinking of but it doesnt perform miracles...