I have a 5.5 x 10 trailer with round tubular sides on it that are about a foot high. I plan on doing alot of mulching this spring and need to be able to fit 3-4 yards of mulch on it. The trailer has a 3500 lb. single axle with a ramp gate now, built really well. I would like to add sides on it to be able to pile the mulch higher without spilling it out the sides. Any suggestions on materials to use or basic plans would be appreciated very much.