Hi Bill,
the case of my watch is approx. 33 mm in diameter and 38 mm from lug to lug.
The reason why I mention two reference #s is because from the Omega vintage site the stainless steel case of my watch seems to be of ref.2667, while the dial of ref. 2814 with red seconds hand.
I will try to have it opened by some expert and I'll post the pictures, ciao,
Roberto