thanks very much , I am using the standard manufacture cable which is comming from no where( i don't know but will need to chase )

re splitter, how do I get one ?

Thanks

 

Here is my suggestion. Either go to You Tube and look at videos on how to install accessories in a car or take the car to a car stereo aftermarket shop.

You can tap into wires using something like this, although I prefer to solder and not use crimp connectors: