This is the first time we've ever replaced a Concave in a conventional combine, and I'm having some trouble figuring out how to get the darn thing out! Feeder house is off, rasp bars are out except for one so its opened up real well. It looks like there is a rod that runs the full length of the concave in the front. Does that rod have to come out? It looks like you'd have to remove one of the drive tires to do it so I hope theres a trick. Thanks in advance for the help.