So, after a day or two reading, buying some rudimentary tools, I have the X8R installed and working in the DJI Phantom 1 after following the directions in this thread:
http://www.multirotorforums.com/showthr ... -Naza-M-V2
However, instead of the switches chosen by the noble Gringers (author of that thread), I chose the SE 3 position switch for IOC and the SG 3 position switch for GPS-ATTI-Manual flight mode selection as more closely following the DJI controller switch setup. I also hooked up the gain to pot S1 as described in the thread, but this is only for Manual mode I think. Haven't tried it yet, though I did put the copter into manual mode.
So, best as I can recall, I did the following:
1) Flashed and updated the software on the Taranis itself.
2) Attempted to flash the X8R receiver with the latest update, but fried it when I applied motor power to the S-BUS instead of 4.8v (live and learn). So, I ordered a replacement with the antenna combo (whisker antennas included) which did not need to be flashed. I replaced one of the large antennas with a whisker antenna by popping off the cover of the receiver, removing the glue on one of the large antennas, popping it off from its socket, and popped the replacement into the same socket. Needed a magnifying glass to do this work.
3) Took the Phantom apart. You'll need a 2.5mm hex wrench for this (not a 1.5mm as described in one of the more popular videos - the one with crummy sound), and a tiny PH000x40 Phillips head screwdriver to remove the existing receiver. You'll also need an Xacto knife to cut away the glue from the cable connecting the existing receiver to the NAZA controller.
4) Remove the receiver by unscrewing it and cutting away the glue. Clean the glue from the SBUS connector connecting the DJI receiver to the NAZA controller, you'll use it to connect the X8R to the NAZA. I saved the receiver for some future purpose, which I cannot fathom at present. Maybe it and the DJI controller will come in handy for something someday, but I doubt it.
5) Connect the X8R to the NAZA controller with the receiver cable to the X8R SBus port. I put the whisker antenna outside the Phantom through one of the rubber grommets that go through the center of the legs. The other I snaked around at 90 degrees, next to an ESC.
6) Put the Phantom together again. Remember to reconnect the GPS if you disconnected it. Once you put the legs back on, remember to plug in the compass. If you don't, you won't be able to set up your IOC in the NAZA assistant.
7) Connect the Phantom to your computer with the USB, connect power, fire up the NAZA assistant. You have to test all the stick and switch functions to make sure the switches do what you want. You might have to reverse the direction of a switch in the Taranis controller. I won't repeat the other tutorials here. Remember to turn on IOC in the Advanced menu in the NAZA assistant.
Remember, you have to do a transmitter calibration in the Basic menu of the NAZA Assistant, and you have to do a Compass calibration before flying for the first time.
I also installed the FrSky SP-FLVS - Smart Port Lipo Voltage Sensor from Aloft Hobbies.
http://www.alofthobbies.com/frsky-sp-flvs.html This connects to the balance port on your battery and reports the voltage left on each cell of your 3S battery via X8R telemetry. It's cheap and it works great. On the Taranis telemetry screen, I have set up Radio Signal Strength Indicator (RSSI), DJI Phantom Voltage on main flight battery, lowest cell voltage, Throttle timer, and Taranis battery voltage.
I just did a test flight and all works very well. The availability of RSSI and flight battery voltage telemetry during flight operations gives great peace of mind as I almost always operate the Phantom over water. Now, I can extend the missions a bit with greater confidence.
This experience has added to my skills and knowledge and I would be confident now to get a 3D Robotics X8 knowing I could configure and tune it with this Taranis RC gear.