Hello - it's me again...
I went back through the Yaesu documentation and found that the tuner port is actually an 8-pin Mini-DIN on the FT-DX10. The documentation for the Y-ACC-2 cable shows a 10-pin Mini-DIN.
The diagram for the Y-ACC-2 specifies which pin to connect to which sleeve on the 3.5m connector but doesn't specify what the pins correspond to on the radio side.
Taking this diagram into consideration, which pins should I connect to on the Mini-DIN 8-pin connector? I'm guessing the Tuner Sense and either GND or TX GND, but wanted to verify first.
Thanks!
JeffH - W4JEW