shadders, i think our cars are carbon copy's, lol.
There is some kind of connection port at the rear of the HU, more then likely for the CD changer.
make sure when you take the HU out that the gear stick isnt in 'P' or 'N' i scuffed mine a little. try to put it in 'S' however doing this you wont be able to take the keys out of the ignition!
I'll let the guy know when he fits it!
If there is a port for the CD changer, this is where you connect the gateway as it replaces the CD changer.
Once it's done I'll let you know all the details & how well it works. Just hope they can get the part they need!