Lampholder, Double SVCE (700TC/I-2,700TR-2,
          700TF/I-2, 601R,601RG,601F,611,632,642,
          650, 680, 690, 561)
  700-2    Use Prior to Serial #2054736.
           From #2054736 To #3151471 See 7016515.
           Starting With #3151471 See 7012420
600 Series Use Prior to Serial #2054736. Starting
           With Serial #2054736, See 7016515.
   561     Use From Serial #1810000 to #2054736.
           Prior to Serial #1810000 See 7015754.
           Starting With #2054736 See 7016515.