I didnt do it myself, are u joking !
the retrofit was actually a mistake from BMW
They said the car could be fitted with it, but it wasnt prepped
Our mechanic said it was a possibility to prep the car for retrofit, but we would need the progrm from BMW
BMW says this is also a "normal" procedure for non prepped or older models
The parts are going to cost about 12000 dkk +from BMW
then it depends on if the car is prepped or not.
The coding/updating via ISS, then you should be good
labour apprx 6 hrs if all is prepped , another 2 if not, and coding @ dealer rates 6000 dkk