a plurality of {HEAD ~ secondary hopper door members} slidably mounted in {TAIL ~ side} by side relation and parallel with said hopper door for selectively closing off a portion of the discharge slot formed when said hopper door is open 
slidably mounted in
a plurality of { HEAD ~ secondary hopper door members } slidably mounted in { TAIL ~ side } by side relation and parallel with said hopper door for selectively closing off a portion of the discharge slot formed when said hopper door is open
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH