what wire harness will i need

just hard wire it in , all you need is a multimeter to see which wire does what

 

nah mate should be easy, there is some posts on here about it but you just need the ISO male plug which will plug straight in, but I had a Calais and i had to snip the loop that the ISO plug had made for the power aerial to get it to work properly and also the acc and constant power red and yellow also needed to be swapped so before you solder them up and click in the head unit fascia thing just make sure you set some preset radio stations and it keeps them when you turn off the ignition and open the door and the power gets cut to the head unit, if the stations dissapear you have the acc and constant power around the wrong way and its not getting the "constant" power for the radio presets and clock. You dont need to pull the dash off either, just make a tool (which is also here somewhere) out of coathanger to slide in and pop the old head unit out, take out the cage it sat in and the new new plastic holder and head unit mounted to that should clip straight in.........there is heaps of posts on here if you need more info, thats how I found the info for mine. You wont have steering wheel controls though.

 

steering controls are the best.. after driving my car i try to use them in my excel and then feel stupid