I am planning on building a tool cage for the front of my 5 x 12 trailer. My trailer already has pretty tall sides (2 foot). My dimensions will be 24"x24"x64". Should I go with the same size angle iron that the trailer is made of (2")? or should I just build it from square tubing? I am going to raise it an additional 10 inches off of the top of the trailer. My main question is....angle or square tubing? What size? I think I am going to have the door on the front and swing down with chains.