Considering the FPV screen has a single 3.5mm A/V input connector, running a pair of common A/V RCA cables for video and audio between the VRX and screen seemed a bit clunky.
The lid was taken off the 1.2G receiver to see if a 3.5mm stereo socket could be mounted.
This stereo connector would provide video out and audio out via the one lead, and not two leads.
A 3.5mm stereo socket would fit in between the RCA sockets, with +/- 0.5mm to spare either side.
A hole was carefully marked up, and drilled out using a bench drill press.
Given the tight tolerances, don’t attempt this with a hand drill.
3.5mm stereo socket was pre-prepared with wires for video out (Y) and audio out (W), and covered with heatshrink.
Ground connection would be achieved via the grounded case.
It was easier to solder the yellow wire (video) to the video out RCA connector tab if the electrolytic capacitor was temporarily removed.
With the 3.5mm stereo socket wired up, and lid back on, the 3.5mm socket does not prohibit the use of the original RCA connectors either side.
Due to the simple nature of paralleling the connectors, either the RCAs can be used -or- the 3.5mm combined output, not both at the same time.
The single cable between the VRX and the screen is just a bit “nicer” than a dual cable.