Guys, not sure if this helps, but I have just installed my door sills and really happy with them.

The way to tap into the power for the sills is from the drivers side pillar, (if you r in the UK) easy to take off, just unclips off, you shall then see the cable loom in black, strip the tape off the loom, about 1.5 inch and you shall then see the wiring.

Doing it this way it neater and wires can be soldered for a perfect job.