I took up the bench in the dinette and can splice into a wire feeding the LP gas detector and mount the recep beside the inverter. Bought one with inline fuse so if it blows I'll have to access that space to replace it. I've found that most auto parts stores and radio shack only sell under dash mount types not flush mount, so will go online to find one and maybe get overload protected type too.
Haven't had time to look behind the TV jacks yet, that would be the best location.
Last time i tried to charge the phone in my Tundra it was dead unless the key was on.