Yesterday I completed the installation of the inverter and a second battery. The wiring from the inverter to the Television/Blu-Ray Player turned out to be pretty easy once I removed the wall between the basement and the back of the cabinetry in the kitchen. I ran 14/2 cable from the battery location to a dedicated wall outlet I installed right behind the TV - I used a white outlet to distinguish it from the black shore power outlet. The stiff cable made routing much easier! I mounted the 180-watt inverter on the back wall of the front storage area, within 18-inches or so of the battery and wired a three-prong male plug to the 14/2 cable.
The dear wife decided she did want a second battery installed, so I bought a Duracell 27DCX at Sams' Club. I mounted a plastic tote that I had which was big enough to hold both batteries over the stock battery box and secured it to the metal floor with a few screws - I added a piece of Luan for a bit more structural support in the bottom of the tote. I then cut a couple of holes in the side of the tote for the battery cables, mounted a PVC fitting as a vent on the tote's lid - the vent hose clamps to it and runs up to the stock outside vent cover, finally I added a couple of 1" vent holes in the bottom and installed the batteries. The bottom vent holes align with the bottom of the stock battery box, so I have have both lower and upper vents to allow for good ventilation.
I disconnected from shore power, plugged the wire into the inverter and powered it on, then checked the TV/Blu-ray - everything worked perfectly.
The next step in the evolution would be AGM or Lithium batteries and a larger inverter IF we wanted to run anything other than the TV/Blu-ray player....but that can wait.
I appreciate all the advice and guidance I was given through other threads in this forum...it really is a gold mine of info!
God bless y'all.