The same thought had occurred to me, given the number on the case back. I find that unlikely, though, for two reasons: (1) the replacement parts (dial, hands, bezel, bracelet) would presumably have to have come from AP and I can't imagine the company would agree to "convert" a watch in that manner and (2) the cost for those parts would presumably have been quite high, and the work done at a time when it would have been just as easy to buy an original steel 5402. I remember a time when steel 5402s in good shape could easily be obtained for a few thousand USD ... why would someone have gone to so much trouble to convert the watch?
I will be curious to see what AP says. I understand that the records at the company do not support the production of "pre-A" 5402s, but I put my faith in the memories of the "old timers" at the company who originally said otherwise ...
Kind regards,
Garrett
This message has been edited by grkyle on 2012-01-06 05:27:53