I do think a converter that is battery powered is the way to go! I put wiring into my Altima for a trailer and used the power I put in for my Subwoofer to power it. It just senses the signal from the cars electrical and the load of the trailer lights is on the power from the battery, this way you don't risk overloading the cars signal, parking, or brake wiring or shorting if something happens to the wires. I tapped the signals off the wire harness just before it splits to go to the two sides. I was very glad because the first time I plugged a trailer in there was a short that blew the fuse going to the adapter. I'm glad nothing happened to the cars systems, you really don't want to mess with that.Just got a small 4x4 utility trailer from Craiglist. How did you wire up your brake lights? The U-Haul guy said the only way he could do it was to do a custom job with a wire all the way from the battery. Seems chaotic.