3 M L & C said:
I cut mine to fit tight. And cut around the middle door and then in the back there is a little notch cut out of the mat on each edge where the back post is on the trailer. Mine kind of fit like a jigsaw puzzle. It took a little work but a new utility knife blade works good for cutting them.
That is how mine are also. If I do it again, I would like to find mats as wide as the trailer. The mats I bought were 6 feet long, my trailer is 6'8" wide.

I puzzled all the mats in, so I don't have just one side with a narrow strip.