Finding +ve in Tuscan boot?

[TUS 373]

I have been playing around with my DAB tuner and autochanger that came mounted in the boot when I got the car. These were installed by a TVR dealer who does not exist any more.

I noticed yesterday that when the autochanger works, the boot light glows!! I also noticed that when the boot is open, the light does not come on unless the headlights are on.

I have dug around in the wiring and found a connector that was not done up - on connecting it, the boot light works as it should i.e. boot open - light on, boot close - light of, all regardless of the headlights.

Back to the autochanger: it still makes the boot light glow when operating. I pushed the boot latch down to fool the car that the boot is shut and light is off, but any operation of the autochanger causes the light to glow, albeit dimly.

I have checked where the power connections go from the autochanger: one goes to a black earth on the offside rear brake light. The other, with an inline fuse, goes to a blue wire near the boot light.

So, guessing: I need to re-wire the positive somewhere into the cat's knitting of wires near the rear lights.

Please can someone tell me where is the best place to do this that will not intefere with the correction function of the car's lights - either internal or external, and what colour wire should I be aiming for!

Many thanks..

[tricky 100]

Better of running a direct fused lead to the battery , quite easily run it under car tapping or cable tying to the chassis as you go.