"rkscott".....Our Monaco had a Magnadyne radio that split the speakers the same way. If you're ready for an upgrade, you can add an inexpensive home theater system ($100-$200), place it in your component cabinet and then just run the speaker wires connected to the radio to the home theater system. The biggest job is adding some speaker wire to the existing wire and routing it up your "A" pillar to a cabinet.
Years ago, I found an open box home theater system at Best Buy where they had been hard on the speakers. Since I didn't need the speakers, it worked out well.
By doing the above, you can also upgrade your dash radio without worrying about buying something with a similar system.
Don & Mary
2014 Newmar Dutch Star - All Electric - 450 ISL
2016 GMC Canyon 4WD Crew Cab