Ok lets run through the relay wiring for your circuit as i see it should be..
1) Battery Positive feed to 30amp fuse connect to terminal 30 on relay.
2) Light bar feed wire connect to terminal 87 on relay.
3) Battery earth connect to terminal 85 on relay.
4) Switched live connect to terminal 86 on relay.
Switched live circuit as follows :-
Run a wire from your Battery to the switch your using to switch on your light bar lights.
Fit an inline fuse between the battery positive and the switch for safety and as it's only switching the relay coil a 10amp should be ok.
The wire from the other side of the switch is the switched live connection 86 as above in (4)
Instead of running the wire from the battery you can pick this feed from your Ignition switch without any problems as this will kill the lights when the Ignition is switched off which is why you probably wired it like that to start with
The light modulator circuit i am unsure about as i have not yet fitted one.
They don't seem to have taken off here in England yet, Pity because they look like a good idea