Bob, you might want to read chapters 15 and 16 of Bob Flexner's book, Understanding Wood Finishing. The problem with a question like this is always that there often is a bit of difference between how you see the finish and how it really is. That's why a graduated approach, starting off with mild cleaning and working as much toward reamalgamating the finish you are comfortable with, is the overall best way to proceed. The tips he presents for continued caring for your finish are very valuable if you love wood. Your library probably has Bob's book.