Sorry for the slow response. I was out diving in the South China Sea with my NA-GH4...
Seems like you have the answer you need.
Initially I bought the M16 vacuum valve for the larger port at the front, thinking that the M16 port is more "out of the way" of the top controls. I use the Mode dial often to flip between 3 custom settings that I have created for different shooting situations and to bring the settings back a known starting point whenever I have been fiddling with some of the controls.
However, once I have the Shogun in a housing, I will most likely have to buy the M14 vacuum valve for the rear door port and use the front M16 port for the HDMI cable, as the M16 port is closer to the camera's HDMI socket. I'll cross that bridge when I get to it.
Thanks for the reply.
My Nauticam housing and the rest of the toys will arrive in a week, I hope.
Can't wait to mess with it.
I tested the GH4 with 12-35mm Panny on land. Using 4K, 3840 pixel, focus is slow but it hunts a bit even when subject in middle field.
Also being a camera type lens and not a camcorder or say an RX100, zooming on a subject with bright background will cause insane flicker on the bright areas....ha ha ha.
Since it is mirrorless, I wonder why the video focus is not as smart as my Sony NEX-7 and flicker free like NEX-7 when zooming.
Anyway, overall I am happy with new nice toys to play with....
Thanks n Dive Safe