Thanks Bullitt, that's makes sense. Great that we are getting to the bottom of these lovely watches.
PS. What is OM magazine?

Stewart

: Stewart, we're talking about 1972 story.
: There was a passage from 1163 to 11630.
: For me there was a lot of "test watch" from 240 to 245xxx
: serial.
: Jack Heuer told me that they test a lot of solutions in that
: period, as you can reed in the full interview in next OM
: Magazine issue.
: So we can find 1163P with 2 different dials and 2 different
: handset, 1163 OB with 2 different handset and, don't forget,
: bezel with or without dot.

: For me, looking these examples on my hands, all these watches can
: be considered "correct" when we talk about 240-245xxx
: transitional range.
: IMHO, from 243 to 245xxx we can find on 1163 the 11630's handset.