The monitor is released from the headrest via a tab accessible through the bottom holes, simply push the tab towards the top of the monitor.

This is the controller hot glued to the back of the screen

The first thing I did was trace the whip pinout to the connector on the board, then I soldered a TRRS connector.

As it turn out, this was a horrible idea, the TRRS cable i got and hacked up was non shielded, and there was a terrible interference that showed up on screen

I would need a different solution...

On the B+ the points I need are PP26,25,24 and ground

using the cable that came with it, I cut it and used its shielded cable and soldered it direct to the RPI