I had for a while experimented with upgrading the TAZ 6 to use a BLTouch instead of the nozzle for leveling.
User Narosenberg (Thing 2985617) went to a considerable amount of trouble to put together a "kit" of sorts and full instructions on how to upgrade the TAZ, which was really cool and the basis for this.
While I have IT-Works 3D Titan Aero heads (fantastic design and amazing company, BTW), as required by Narosenbergs original design, I didn't like that installation of his mount would basically "lock" the print head in place. If you wanted to change your print head, it forced you to disassemble the BLTouch. That wasn't really ideal for me, since I switch between 2.85mm and 1.75mm, and have different nozzle configurations on a few different heads. Put differently - I'm swapping heads often.
I took the Original TAZ 6 X-Carraige and modified it so that it has an "accessory rail" on the left hand side. Fortunately there is extra clearance on the design of the Taz 6 so I could get away with this. I then modified Narosenberg's mount to include hidden wire routing (who wants to see wires?!) and to fit this "new rail". With this mod, you are able to mount the BL Touch to the modified carriage rail without interfering^ with the head mounting. (^ For standard heads, typically; will not fit a dual extruder, YMMV)
IF you use this mod, I'm pretty sure it will void your warranty. Regardless, you are using anything here "at your own risk", obviously. I think you will also need to modify the version of Marlin / the instructions that Narosenberg's Marlin Mod as this will change the offset of the BL Touch sensor relative to the head vs. his version.
Hope this helps someone!
I ended up reverting to the out-of-the-box leveling the TAZ offers, because I also occasionally use the dual extruder, and because that thing is so huge, there's still not enough clearance for it without removing the BL Touch. Plus, the Dual Extruder has a different calibration sequence, so it's another whole can of worms I just couldn't be bothered to get into.
Hope someone can get some use out of this!
Printed on a Taz 6 with a 1.75mm filament (YES - It's true!) using IT Works 3D Titan Aero Pro head (https://itworks3d.com/)