I have had the BLTouch sensors sitting around for my Monoprice Maker Select Plus and Wanhao Duplicator i3 Plus, but have never gotten around to installing them - today is the day. We pass a lot of pitfalls on the way, as I have some trouble with the wiring, the 3D printed bracket I have selected is far from perfect, and the firmware(ADVi3++) needs recompiling, but we get there in the end with all the auto bed leveling goodness.
Newer versions of the ADVi3pp or ADVi3++ firmware may have the feature to specify the location of the leveling sensor build into the menues, at least I saw that as a feature request on their github - https://github.com/andrivet/ADVi3pp
You need different firmware versions whether you have the original BLTouch or BLTouch V2, or the newer BLTouch version 3 or newer still. I have a BLTouch version 2 I believe, BLTouch3 wasn't supported when I did this install, as far as I remember. Also make sure you get an original BLTouch from ANTCLABS Inc, the clones are inferior products, which are not nearly as precise, and you will most likely regret buying them.