... and of course as soon as I ask for help I find the answer. Don't try to push the plug vertically into the socket on the Airport board, start it at an angle with the cable running up and away from you towards the screen, then rock it back horizontal and it just clicks into place. -- Sam

The inverter cable was fine if a little fiddly, but I can't get the antenna cables back on at all - anyone got any ideas? Even with bright lights and magnifiers I can't see why they won't go back in. (And I don't know why ifixit thinks I'm called facebook -- Sam)