Thank you very much for the reply! Yours is simple and light. I like it. I like the idea of something light and small too because there's less blind spots when you drive. And the idea of getting into an accident seems more likely with something really big.
What do you do if the flatbed trailer you are adding sides to doesn't have those little stake post slots already built onto the frame and you are trying to add enclosure to the same small trailer? Specifically what I'm talking about is adding 'enclosure' of sides and roof to like a very small 6...