Allright i replaced the fuse for the wire on the radio which provides constant power, then my dash lights went out, so i grab my test light and the only fuse thats bad is the tail light fuse, so i check my tail lights and there out, so i replace the fuse and as soon as i turn on the headlights it pops, does anyone know what else is on that circuit, and where the ground is for the tail lights?

 

Mine was doing this too. In my case, where the harness comes out of the body, right behind the tail light, theres a vertical piece of (body) metal that the harness was resting on. Over time this had worn through the harness, and into the wires, grounding it out.