Go to your local auto yard and get a 7 pin connector off of another vehicle. I mounted that to my tongue and wired the 12 v to the running lights ( I know many don't like that but we love the lighting around the TT at night, rarely are we in an RV park). The wiring has an inline fuse and a switch. I just unplug from the TV and plug into the connector on the tongue. In the evening flip the switch and you have lights. On the last trip in flip the switch off and go to bed
I have plans to make it better and cleaner but I will save that until it's done.