Once you've released the original oil pan, you can begin to clean up the oil pan mating surface. One thing to note: There are two alignment pins which help to locate the oil pan with the bottom of the engine block. It is possible that one or more of these pins will stay with the oil pan cover rather than remaining in the block. So, check to make sure to remove any alignment pins which stayed with the old pan and reinstall them in the proper locations on the bottom of the block.