Like the solution and thing it will do you fine.
I was wondering about the top tread metal thickness so thanks for posting that. You should get by without any reinforcement, but keep an eye on it. After the first trip or two, put a straight edge on it making sure you aren't starting to see some bending. If you do, you want to catch it as soon as possible before you stretching the metal. Just add a heavy wall 1" angle or tubing under the edge and you won't have to worry about it again.
By the way, neat "toy" to haul around. Have fun at the fairs.
