I just wanted to thank Rose Marston of MAX BMW in NH and Luis Roth for the help both have provided to me in my quest to retrofit dual horns on the RT. Rose quickly set me up with the parts I needed (and a pair of K1200RS mirrors) and even emailed me a copy of Luis' instructions for the mount and electrical connection.
I also used Luis' instructions for removing the front nacelle and they were spot-on. Great folks here in our community.
Thank you all!