Anyone add extra lights to their SN?

I added a light under the dash for finding equipment stored under there or for working under there when needed.  Switching to LED lights would certainly draw less power and are a good move.  I will put that on the to do list mostly to reduce battery drain.

I was going to do that anyway, but was thinking of adding extra lights.

About a week ago, I was at the lake with the kids and we went out for a night cruise. We stopped and anchored at the sandbar with several other boats. I didn't want to leave my nav lights on because I didn't want to run down the battery, but I didn't want to possibly cause an accident either. The previous owner added a second battery with an isolator so they could run the stereo without worry and I removed it. I'm going to put it back in, but I'm wondering if there is a way to add some LED lights preferably to the outside without drilling holes in my hull? My boat is a 1989 2001.