So indeed it is an A, B, A+B switch and uses impedence matching by switching the speakers either direct (A or B) or connecting them in series (A+B) so that there is never any more than 8 ohms on the channel. Initial plan is to set the radio to the front channel and use the switch between inside/outside. The power is reduced in the A+B configuration but not a big deal as we don't turn it up so loud that we are entertaining our neighbors. If the weather cooperates will complete the install tonight after work.
Walter & Donna
2011 CC LB RAM 3500 CTD 6.7L DRW
2013 Cedar Creek 38FL
2014 Days Camping: 35