I have never heard of anyone in a TTT being stopped or cited about wide trailer lights. Also I want to be careful not to spoil the clean arrangement of lights at the back of the trailer. To me the front and rear clearance lamps on the fenders are more important for 80" wide teardrop trailer than the rear ID lights. In case another driver does not see the wheel sticking out at night.
I did contact Little Guy and they had gotten an opinion from someone at NHTSA that the three lights in the rear center is more of a tall vehicle thing, as in tractor trailer. These usually have the three lights in the middle at the top of the trailer and clearance lights at the corners, a five across arrangement.
But then most 80" wide boat trailers do have the three lights, down low on the frame below the boat. And more confusing they often lack the front and rear clearance lamps at the widest point on the fenders. I admit to being totally confused.

I find myself looking at trucks and trailers for the lights. There was a tow truck recently, the kind with a tilting platform to carry a car. It had the three rear ID lamps below the platform, but I did not see any rear clearance lamps.
I imagine that commercial vehicles generally need to be more careful about having the 80" lights done correctly, while there seems to be little if any enforcement for privately owned teardrop and boat trailers.
If I can add the rear ID lamps in a way that looks alright, I may do that but am still not sure. If I do put them on I will add a photo in this thread.
In an earlier topic Nitetimes posted a link to a photo of his light arrangement.
http://www.teardroptrailers.us/TDbuild/slides/TD05.html
And this one is by MacGyver with the three lights on top.
http://tnttt.com/album_ ... c_id=45893
These are the only two of which I am aware. A 5' wide teardrop would be just under 80" at the wheels so it may be that most do not need the lights. My trailer is 6' wide and 90" at the wheels.
Bill