Interesting article on TWOK and Space Seed on io9 the other day: http://io9.com/inside-secrets-of-the...h-of-457250013
The fact that "II" is in the title is a clear indicator that it's at least acknowledging that it's the second movie. Whether this adds anything or not, I used to have a Leonard Maltin film guide where he reviewed, what seemed like, every movie in existence up to that point -- in this case, the one I had was from 1998. On his Star Trek II
review, he mentions the film was released as "Star Trek: The Wrath of Khan
That's not true, is it? Was the "II" ever omitted at any point? I've seen the original trailers, posters, and TV spots and not once did I ever not see the "II" in there.
I wasn't born yet when the film was released, so.
I've seen prints where it's just "STAR TREK: THE WRATH OF KHAN." Too, there's promotional artwork and images that did not have the "II" yet.