Wiring in the Power
Time to wire in the power connection. Go back to the wires you exposed earlier, remove the tape and pull the wires out of the black casing. Separate the black and white wires we're going to be using:
Now, carefully strip a little bit (half an inch or so) of insulation from the black and white wires. Do this at different point in the wire to minimise the odds of a short developing:
Strip the ends of the red and black power cable that came in the kit and twist it into the copper wiring you just exposed. (Black to black, red to white).
This is optional, but soldering the connections will make them far more sturdy and reliable:
Now go mad with the electrical tape to seal it all up. Make sure you tape the two exposed sections separately first, then wrap it all up together using the black trunking that you opened earlier.
Run the red and black cable back into the boot and through the hole that the sensor cables are going through already: