We just removed a head off an 85 CRX Si because of a broken timing belt. The heads is being rebuilt (4 damaged valves). Trying to get the block surface "shinny" clean seems like an impossible task. I can get the gross gunk off with "gasket solvent" but the underlying aluminum is discolored light brown and really dose not want to come any cleaner. Can I proceed with the new gasket or do I need to do some more cleaning? And if so with what? wolf