Thanks again Jeff.

I've been doing some research on the 980.004.

I've discovered that there are 3 variations of this model.... (I have variants 1 & 2)

Variant 1.
980.004 With a blank chapter ring.
This model has no minute markings on the chapter ring.
Day/date is standard black text on white
Has the ESA 536.121 movement that is present in the early 980 series oversized divers
Bezel markings are PVD printed onto the steel bezel
*I have this model, and know of a Dutch collector who has one too.
link here: http://heuerville.wordpress.com/2010/08/16/heuer-diver-980-004/

Variant 2.
980.004
Has minute markings on the chapter ring
Day/date is standard black text on white
Has the ESA 536.121 movement that is present in the early 980 series oversized divers
Bezel markings are recessed & filled.
The word 'Quartz' on the dial is italic
*I have this model (not photographed yet), and if you hunt around google you will find other matching variants.

Variant 3
980.004/1 (as pictured in this catalogue)
It is actually marked 980.004/1 on the caseback.
Day/date is unusual white text on black
Has the later ETA 955.114 movement that is present in the 1000 series marked 980 series oversized divers
Bezel markings are recessed & filled.
*link here: http://classicheuers.blogspot.com/2010/03/very-rare-heuer-diver.html
This particular version seems to have a domed crystal (or is it the light?), I don't know if this is standard.

Other notes:
There are some very minor differences in the hands across all variants - the length of the lume filled area differs slightly.
All versions I have seen share some commonalities... they have a 21mm bracelet with unsigned clasp, the crown is unsigned (like the other divers of this period), strangely the m'ments are all unsigned too.
I presume that variants 1 & 2 came before the variant shown in the catalog due to them having the earlier movements.

: None of our favorite mechanical chronographs here, but some
: interesting watches . . . "twin times" (analog time of
: day and LCD for the chronograph, with the same movement as the
: Memphis), the mysterious 980.004, and the phosphorescent dials
: for "night diving".

: Jeff

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