If you can find a radiator shop that still has a vat of carbon tetrachloride than I would recommend letting them dipping the engine block. Remember, though, you MUST make sure it is clean afterwards since carbon-tet is fairly toxic. Otherwise you can use a high pressure hose charged with a mixture of Simple Green and water. Just be prepared to scrub.
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All this worldly wisdom was once the unamiable heresy of some wise man. -Thoreau