glowworm migo

Afternoon, I am fitting a Migo set-up to Glow-worm Ultracom hxi, and need to link RT-24. But I can't see how to do this on this circuit board. Other PCBs make it clear and easy to do this. Photo of PCB attached. Thinking the link will be at X19 on mid left but which pins? Help please, cheers

I have just had my ageing Potterton 15he boiler replaced with a Glowworm energy7 18r. Rest of the system is a standard s-plan unvented system with a Drayton LP522 controller and on-off thermostat in the living room. I am thinking of replacing the controller and thermostat with a Glowworm Migo...