Nate, I don't believe there is such a thing as a digital line voltage t"stat. You may be able to find line voltage t"stats at old hardware stores or surplus places. You would have to construct the duct work as the air cond. mfgs. do not make this. Usually the ductwork is installed in the ceiling and then a ducted model of a/c is installed. Good luck and be safe.
Mike, RVIA & RVSA Certified Master RV Technician
Amy, Dr. Assistant - Roxie & Mei Ling, four legs each
2000 Gulf Stream Scenic Cruiser 450 hp & 1330# torque
06 Saturn Vue, 06 Chevy Z71 4x4 & 2014 Corvette Z51 M7