We have a new 2021 Trail Runner 31db. 36 ft long and one Dometic AC with thermostat. I am fairly handy guy, and with some assistance I believe I can add a 2nd unit to the pre-wired location. It already has a 20amp breaker, and it appears the wiring is ran to the vent I'll be placing it in. Have you done this? Is there a second thermostat location, or are both units ran by a single thermostat? Or do you have to get a manual control for the bottom of the AC unit? Thank you for you help!