I did get the buttons added to the steering wheel
I have all the sensors, I have forward collision, lane assist, and blind spot monitoring. I found this programs a little different then my Ram. I have a person who is going to help me with the conversion later this month when I get a grey cable required for the programming. I ordered the cable it just hasn't come in yet. I also ordered the correct adaptive cruise buttons since my right button seems to be wrong for the US market.not sure you can just add the buttons and change the computer for adaptive cruise control to work as you will also need the front mounted radar / sonar (not sure the correct terminology) as it is separate from the lane assist and parking sensors. the wiring harness may also be different as well to account for all of the required components.
I found it out the hard way. I am going to do the exact steps you suggested the next time I try it.This is how it should be done.
1- Backup your configuration
2- Enable the option you want
3- Do a proxy alignment.