Response to AJTIII: My throat width is the same as all other machines.The problem seems to be the width opening of the new header.As for as the performance of the 600 series head it is GREAT! With all the problems we had getting it to hook up to my combine it was worth it.If you are going to put this head on a combine older than the new 60 series combines the very first thing you have to determine is if you need a wedge kit.This is determine by taking a measurment from the ground to center of your lower feeder house shaft.A wedge kit will run you $600 plus If a wedge kit is needed then you have to torch your old hook up plates of your new header and weld the wedge kit on.My dealer said if he had to do it over he would of changed the back wheels and tires on my combine, so that we would not had to do all the torching and welding.The head runs very smooth,and the faster sickle cut is great. The flighting is thicker and the auger is a biggeer diameter.The new hydraulic flex also worked great regardless of what pressure you have set the header will shave the ground.I also noticed that it feeds very smoothly with little or no bunching.