David,
Call S&W at 1-800-331-0852 and ask to speak with Gene Sypek. He is one the master gunsmiths on revolvers. He's a great guy to talk to and should be able to help you. He's worked on several of my Smiths over the years and I would highly recommend him.

Just in case you do send it in, which I would highly recommend, S&W shuts down the entire month of August for everyone to take vacation.