According to another poster, please don't use even fine steel-wool or emergy cloth to clean connectors.
Microscopic bits of steel-wool get embedded and corrode. Confirmed by a microscopic visual inspection. Erasers are also a no-no for an electrical cleaner as well.
He suggsted using a 3M "red" Scotch-brite which leaves no particulates, followed by a dose of the proper DeOxit for either "tin" or "gold" plated connectors.
1988 360TE AMG