Brain box pins

drill a small hole in a pencil eraser, place it over the pin and rotate or chuck in a drill. contact cleaner is the best, then cycle the plug a few times. Use some dielectric grease in there to encapsulate the contacts and prevent oxygen contact, that causes oxidation and corrosion. Get a tube from a cable TV installer. a little goes a long way. IIRC Mopar used axle grease in the pickup truck bulkhead connectors.