Hello I came up with this way of installing the ESCs that I found makes for a neat tucking away of cables. Doing them one by one I noticed that by having the cabling take a natural route around the power board my routing ended up so that while an ESC is located underneath the power plate on one side, its control cable connect to the power board control outlet on the opposite side.And as it happens so does the motor cables. So a motor will correspond to the power board speed control connector on the same side as that motor. Should it turn out sides needs to be swapped around to match the APM sw then it´s simply a matter of swapping the control leads around and these have plenty of length. I connect the input power cable of each ESC to the socket located 90 degrees clockwise ahead of the ESC. Which power socket you chose does not matter from a functional point of view since they are all interconnected. Use the one that makes for nice cable routing as I did here. I used four straps in total to hold wiring neatly. My control cable wiring is wrong in the photo, but I´ll swap them around.
Per request, here are photos with the dome and platforms attached. I have some more electronics to mount before takeoff, but you get a sense of it.
It seems in the early preproduction hardware the lengths of various cables were different and there was no provision for in-arm routing. It would be possible to reduce the "nest of wires" further by shortening wires to the optimal length for this method and doing lots of soldering/shrink tubing jobs. But that borders on "aesthetical fanatism". The above show what can be done with the production kit components as-is.