I'll go out and take a picture of one that I cleaned up myself. Dark spots on the mating surface? How dark? If its remnants of gasket material, use a scraper...just hold it at an angle that will keep it from gouging the aluminum. Another good cleaner is carb or brake cleaner...spray it on heavy and wipe with rag using plenty of pressure. There will be nooks and crannies on the exterior that wont come clean due to the porousity (is that a word?) of the casting...no biggie though. Your main concern is the deck and the combustion chambers. Keep it at...one thing is for certain- not a small quick job.
~Darin <img src="/forums/images/graemlins/baby.gif" alt="" />

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