Just a short answer, Many folks here will probably say this subject has been talked to death with forests of trees sacrificed for paper to supply the reams that have been written. So just surf the net for information on cleaning and lubricating a shotgun! On a personal note soaking a complete action in that wonderful liquid kerosene us Brits know it as paraffin I feel this should only be a prelude to a full strip down and clean. Otherwise the Kerosene could or more likely move fine grit and other contaminants further into the moving parts of the action.
