Just been having a bit of a nose round in the engine bay and this is what I've found so far, looking behind the nearside lights..
Pin10 of the headlight connector (grey/black wire) does seem to be the sidelights feed and therefore used for the white 'trigger' wire. 12v when headlight switch set to 'sidelights' with ignition off, 0v when all off.
There is a connector below the headlights (shown in first pic, just to right of headlights connector) which the installation instructions may be pointing to for the red 'switched live' wire.. Anyone know what this connector is?
Pin2 of this connector is the brown/black wire. I haven't tested voltages on these though.
Is it OK to take feeds to both of the LED control units from this one side? Forgive my ignorance with all this!
I'm too hungry to do any more now so you'll have to wait!
Any more thoughts/suggestions gratefully accepted!