68 Dart marker light junction location

[Sdriche]

I have a 68 Dart with the right rear marker light out (no power). I have the wiring diagram which shows all the black wires being junctioned together which is where I suspect the short is. Does anyone know where all the black marker wires junction together? I know I could splice in the trunk but wanted to keep it clean looking. Thanks.

 

[RedFish]

In most cases there is a weld splice buried under harness tape in the trunk. Park lamps and tag lamp all together.