Firstly are you riding at night, because you're not going to blind anybody in the day and there aren't too many tunnels there either.
I don't think the local scuffers will be in the least bit interested in your headlight.
If you feel you have to do it, just put it in the garage, turn the garage lights off and tape it off with good sticky insulating tape, but I don't think I would bother if you're daytime riding.
Upt.