This case is considerably earlier than the dial and hands, so there is no doubt that there is some "marriage" or replacement of parts / components.

If the case number had been in a considerably higher range, then the watch may have been all original, so cosmetically / on its face the watch does look OK (i.e., Heuer made a watch that looks pretty much like this). But the serial number [and -- to the expert -- the "big ears"] tell us the real story.

Jeff

+++++++++++++++++++++++

: I'm now getting even more confused!!! So does that mean that this
: was an 1163 model sold as above or still likely to have been put
: together using different parts?

: I must thank everyone again for the replies, I used the forums in
: the past - maybe 5 years ago? And there was nowhere near the
: amount of activity there is now!