it is pretty simple really......THERE ARE NO EMPTY CONNECTORS FOR THE SPEEDO. Just unplug any dark solid green and any brown in there and put this new harness in series. On the plug you unplug you're going to unplug a male and a female. On the speedo wiring you're going to have a male and female. simple plug the new harness into what you unplug. the green is a ground and the brown is a switched 12 volt that runs the tail light. I guessing the speedo has a light in it that comes on when the lights are turned on.
here look at my colored wiring diagram, sorry it's so small.
these the same instructions you have?
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