An update for UK users:
I have just successfully achieved this retrofit but UK RHD owners need to be aware that you have to order the following part numbers. My vehicle is a 2013 F31, so check with your parts supplier if there are differences for other model years.
1 retro kit - B66.20.2.338.070
4 sensors B66.20.9.261.582
1 switch B61.31.9.252.921
1 holder kit B51.11.7.324.343
1 cable set B61.12.9.313.607
Note that -
1) switch for LHD cars, B61.31.9.252.912 (last 2 numbers transposed) will not fit a RHD car. BMW are being their usual un-cooperative selves with me, refusing to take back my LHD version I ordered in error, so if anyone on this forum wants a bargain brand new switch for a LHD car please contact me on
d.r.chadwick@btinternet.com.
2) the retro kit includes only part of the items you require. I do not understand why this is the case.
3) the sensors need painting with the colour of your car. You can order pre-painted ones at c£250 ea cf £100 ea for unpainted. Total cost parts + labour to fit c £900. In hindsight, far too much money, but it does work very well, integrating nicely with the existing rear system. Much better than non-BMW retrofit, but not sure if worth the extra.
4) I cannot comment on the fitting/software changes as my engineer did the job, but he did not report any problems (possibly because he is extremely capable)