hey, just an idea,
why don't you replace the connector for something modern & waterproof.
like these http://www.iem-services.co.uk/search.as ... seal%27%27
the only issue is if you want to keep the car "original".
every time you clean a connector it will rust again in couple of weeks ,
these cost only couple of dollars, and once you replace them you can forget about cleaning the connectors.
i know that meddling with the wires can be pain in the ass , but look at it as a long term fix.
especially for those connectors exposed to the elements