I want just to share information with you. I have AR 156 2003 (internal FL), engine 1.6 120HP. Because I don't have cruise control I have study that problem little bit and I have find all necessary information to install it, even I didn't have white connector under steering wheel.
ECU in my car is on engine, so I was put pins in empty space in ECU connector and pull them under steering wheel (4 wires needed). Unfortunately, I didn't be able to bay stalk for AR156 FL, so I have bay today some used for AR147 ... so I need to study how to cat it and feet it in my car.
I have try it with some switches (before I have bay stalk) and works perfect.
So, if you don't have white connector under steering wheel and you have skilled hands, it worth to try it. If I have good information, JTD engines have ECU inside car, on passenger side, so it is may be even easier to pull wires.