I ran a JD 4400. Worked really well. I would drop the rear cover under the shoe auger and put some styrofam over part of the straw walkers. This was with a 215 platform. Most of the time I would unload without having to get out of the cab unless it was thin seed. The thicker the seed the better. I'd also take the covers off the 3 little augers in the bin. I'm going to try it with the 7720 and a 220 flex this year. I might be wishing I had the 4400 back. Good luck.