Jeff we asked the same question at a combine school and this is a gleaner engineer's answer. The proto. P1 processors did not have that cover and when the combine would stop there was some straw on top of the cage and even though the engineers proved that the cage cleaned the straw off while working a big boss (white shirt and tie) told them to put a cover over the top of the cage. The engineer told us to pull it off and throw it away. PS. i thought that agco had stopped fitting them. john