[butler-henderson]

The difference is the worm - XO4's have brass worms, X03s have plastic ones. The dissappearing flet pads were more a cost saving exercise than any variant in the motor.

 

[butler-henderson]

Could there have been 2 X03's then? If you look at

http://www.modeltrains.net.au/hornby/service_sheet_menu.asp

then it is quite clear that the X03 came after the X04 with the worm being the difference

Service sheet 81B reveals all
http://www.modeltrains.net.au/hornby/servi...asp?sheetid=198