Shroud Assy,Fan SVCE (501R, 501F)
  501R    Use Starting With #1004775 And Between
          #959920-#960169. Prior to #1004775
          Except Between #959920-#960169 See
          4280510
  501F    Use Starting With #1004775 And Between
          #960170-#960319 And #996400-#996574.
          Prior to #1004775 Except Between
          #960170-#960319 And #996400-#996574
          See 7021955.