hi,
The relay is mounted OFF the pcb, its on a remote pcb
Its a 12V, 2 pole change over relay, with mains rated contacts.
Run a pair of wires from the two pcb pads near the LDR, [which is required for the light/dark control to the opto] to the remote pcb contacts, say contact set RL1/A
Run a pair of wires from the two pcb pads adjacent to the relay driver transistor to the remote relay pcb coil.
The mains rated lamp wiring will be connected to the pcb on which the relay is mounted, contacts RL1/B
Do you follow OK.?