Fitting spotlights - wiring?

[Fazerider]

The green wire you’ve marked ??? can go to either terminal of your bar-mounted switch.
The other side of the switch needs 12V, you can take that from the high beam switch (yellow wire) if the spots are a bit fierce for oncoming traffic. Or the main headlight feed (blue/yellow or green or blue/black) if the spots are aimed down enough (or if you just don’t give a shit, like about 10% of vehicle owners).