Stay supervising in the tuner shop ........ sorry ! hard to type Chinese by their old dirty keyboard. Answer to KK-KAI ,Rep said, The SW lock is standard for all BMW vehicles.
Those mechanics are bolting on M5 rear bumper, a few E60 had been retrofitted here, this's why I trust them to do it . One thing for remind , the standalone bumper leaves an ugly hole in the center , you can see the tire well. Put an extra mesh on it for covering is highly recommend as I did.
Luckily the tuner sell Boron Nitride (an artificial ceramic material for cooling) as well Deal them with a good price to do the coat on Transmission box and oil tank which 535d may need during hot summer days. Hey I found the new car is perfect to have the coating cuz everything is new and clean oil cooler, oil tank and transmission box are all shining new !