I heard some of you were unlucky and don't have 1 so here is how (briefly)
Piece of piss in the end the loom i had does have the wires but confused me a bit but i double checked my findings with the colour codes of the wires on my van and tested My theory by putting a wire to the pin i thought and ground and voila hand brake light on (obviously i took the handbrake off I'm not stupid!)
Ok all you need is a length of wire that goes from the handbrake to the central fusebox (be generous as the conduit bends and stuff. Get a handbrake switch and connector
and with 1 of the wires (black and white) earth it to the body somewhere by the handbrake.
The other wire blue and white (thin speaker type) feed that under the carpet in the conduit preferably it goes from the seat and up the middle of the floor to the centre of the heater matrix.
It is loose then take off the glove box and drop down the central fusebox to show the bcm, there you will see the black and gray plugs c3 and c4 i think,
unplug the black plug and you'll see 2 coloured blocks in with wiring on,
unplug the white 1 it just unlocks and slides out. You need pin 2 far right notice my image there is an arrow going to the left on my picture pay attention to this ok. Ideally you want a proper Ford wire which just plugs in securely but if not you can push the wire in and tape it there it should work.
I hope someone does this mod lol i already have a handbrake and now and have purple plums out in the cold all in the name of science!