There are 2 wires that I don't know what to do with. They are called "key1" and "key2". I understand there are for steering wheel controls. I'm yet to take my current headunit out but I doubt there is going to be 2 wires to directly connect the "key" wires to.
From what I've read online I need to determine if my car has analogue steering controls or digital steering controls. If I have analogue steering controls I need to do something with an SWC which I don't understand. If it is digital, I need to use a patch lead. I have a Kenwood ISO harness with a patch lead but I'm unsure if it will fit (was previously going to install a Kenwood HU).
Yes you need to determine what kind of controls the car has.
In my car (Pajero) when I did an aftermarket unit the wheel was just analogue (just a series of resistors) so I literally just connected 1 wire and ground for the SWC to work (Pioneer unit has a 'learning' mode where you push the button and tell the head unit what it is)
Integration needed nothing other than an old 3.5mm stereo jack (but only used 2 wires) and I just tapped into the wires coming from the steering wheel that went to the old loom for the factory stereo.