[JasonB]

I must be misunderstanding something here.

Assuming the current plug is on the left, then it's labelled Left, Right and Earth, so it's an audio connector, which wire up as in Leo and Gordon's diagrams.

Unless you are going to use a non audio plug, then you can surely just connect it in exactly the same way. The colour of the wires doesn't matter, it's what you connect them to that matters.

If it works okay now then just connect it in the same way and it will still work.