I ran my headphone cable INSIDE the tube and out the end of the tube by the cuff.....I drilled a hole in the shaft above the grip, and then fished a wire and snaked the cable through the hole...To do this method the cable has to be cut, so I simply soldered it all back together and shrink tubed it, and then retracted that splice back inside the shaft...so the soldered cable joint was inside the tube... it was sleek and no big deal at all, probably a lot less fooling around than trying to pull off the grip...
This allowed me to use the same GG NTD phones on either my AtPro or my F70 merely by unhooking the phones from the quick release instead of having to deal with the Garrett phone plug...It was a sweet set up, my phones were all dialed into my ears and worked on both rigs seamelssly...no worrys about water at the socket on account of the NDT's quick pop off is right up by the headphones...
I did the same thing with the coil cable on my F70..Instead of having it taped or wrapped to the shafts, I cut it and ran it inside the tube.... solder spliced it back together...It works fine and the coil wire is internal...
Why I prefer to cut the cables is its nearly impossible to unsolder the small wires at the plug ends....so its easier to just cut the cable, thread the wire through the tube, and then solder splice it all back together...
I bought the NDT's with an extra cable...both with the 90degree standard plug, so one was fine for my F70 just the way it was, and on the other, on the other cord, I cut off that 90 degree plug, fished the phone wire through the AtPro tube, and soldered on the Garrett plug.... see? Easy peasy pumpkin pie!