give yourself a full day on this it aint a quick fix!
Firstly disconnect battery(safety first) next file your under the bonnet disconnect the two pipes running through the bulk head left of the coilpack

right inside the cab we go you need to basically remove everything from the dash. steering wheel, clocks, stereo, centre console, glove box, driver and passenger lower try's etc til it looks somethin like this


*note be very gentle when removing the heater vent if they dont come out easy you havent removed all the screws
once youve removed all the bolt on bits its time to unbolt the dash which in held in by 6 bolt, 2 on either end and 2 in the centre behind the centre console

now gentley give the desh a tug and lift and the sametime it should now be loose but not free just yet behind the stereo and heater controls is a large black plastic box about the size of a cerial packet held in by 1 screw at the bottom and 2 clips, one either side you should then be able to remove this
ok back into the engine bay and unbolt the 2 nuts holdin the heater matrix to the bolk head

now we are getting somewhere