This guy (https://modelrail.otenko.com/retro/vtech-socrates) already made an RCA-Mod on the Socrates, so the pinout was pretty clear and easy to handle.
I designed A small pcb which will make this mod easier and you will also get a back-plate which will cover the hole on the back of the console
|RCA-PCB and Back-Plate|
The board can get screwed to the console and the back-plate can get soldered to the rca-pcb.
Afterwards, everything fits and is ready to use.
I already modified three consoles with this mod.
The price for all parts (without screws) is 10EUR.