Want to put electric windows/mirrors/central locking into my corsa, i av a small problem though.

If i bought all the stuff for the doors, locking motors / ew motors / mirrors n switches for the door paners, i stilll only have 2 wires running through the multiplug on the door.

What would i need to do, replace the wiring loom that goes through the door?

Anyone know how much these cost, how hard they are to fit and where the wiring for them goes, ive read that its just the dash loom, but does this not carry wiring throughout the car (like to the boot) or is that a on seperate loom? N would the new loom off a higher spec car just plug straight into the ecu without any problems?