This may be possible with my Scene Manager plugin. If there are game props whose lights are able to be turned on or off (I don't know off the top of my head), you could add them to Scene Manager's .ini and place them in game.
Edit: Just confirmed this does work for certain props:
prop_worklight_01a
prop_worklight_02a
prop_worklight_03a
prop_worklight_03b
prop_worklight_04b
prop_worklight_04c
prop_worklight_04d
Enable Enhanced Barricade Options in the .ini and use the Enable Barrier Lights menu option in the barrier menu to toggle the lights on and off. I've added these to the .ini for the next update.