Here is the factory fitting instructions for a Nissan Factory Towbar. The same rules apply basically for most of the after market Towvars too. I have fitted an aftermarket towbar to my S5 Y62 without these instructions but YouTube was my friend.
Worth noting is the Factory Loom plug for thr reverse proximity sensors is up in the rear drivers bumper. You can unplug the entire rear bumper from here and don't need to touch any of the sensors to fit your towbar.
I hope that Helps
#The62
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