You could ask Tony at Forte to increase the wall thickness of the tubes, to compensate for a 9'6" beam.

Why 9'6"? If you went 9' you could probably trailer it without getting caught.

I was going to go 9' and thats what the beams are spec'd for, so they wont be that much differient if you go 9'6". Take a look at the 18sq thread, the way they are making the tramp so that it stays attached to the beams and the sides is interesting.

On the beam ends, if you are just bolting it together, you might want to take a tube scrap and glue it into the inside of the beam. The aluminum beams have a second piece of aluminum on the inside, you could replicate that.