mneary,
Thanks for the link. I am not much of an analog circuit person, but I now have a general idea of what is going on.
Nigel,
As best as I understand from your comments, I simply use the Left+ and Right+ signals out of the amplifier. Instead of using Left- and Right-, I just use the power supply ground as common for the speakers. Also, I would presume that because I would be using half the amplifier on each channel (because we are ignoring the Left- and Right- signals), then I would have about 3 watts of output instead of 6 watts. That would solve my speaker problem of the 3 watt maximum power.