Not sure you will be able to get a full 30' spread but you can get the residue chopped up more finely. http://www.tsrparts.com/ I installed a TSR fine cut rotor (double sharpened knives in place of every single blunt hammer) and a TSR knife bar kit (sharpened knives in place of sickle sections) on my older 6620 combine. I also installed the winged sharpened hammers on the ends to get a little wider spread pattern. I run a 20 ft head and do a pretty good job getting it spread across most of the width. Here is the original thread about it. https://talk.newagtalk.com/forums/thread-view.asp?tid=186379 and a follow up with some pictures of the spread. https://talk.newagtalk.com/forums/thread-view.asp?tid=505625 https://wajohnson.com/ Also used to make a bottom sheet that accepted 2 rows of removable knives to help chop better too. Don't see it listed on their page now. https://redekopmfg.com Also sells fine cut rotors and serrated knives | 
JD 9000 series Walker Combine Choppers?
