Hello all, I'm currently building a large tractor and an outdoor run that will attach to it. I would like to make the run just over 18" tall, so I can split my 3' hardware cloth in half and save money. It's going to be basically a square box. I realize 2' tall would be better, but can I get by with 18"? I plan to get red stars when everything is finnished their supposed to be 5-6lbs at maturity, but I've not been able to find how tall they get.