A heads up: The instrumental theme song from Guns of Navarone, rendered by The Skatalites (a rather short-lived aggregation of Jamaican studio musicians) was a *very* popular recording in the ska era/genre. That is, a very popular *dance* number, both ca. 1964/5 when it was released and later during ska "revivals" (1970s, 80s, 90s).

I and my peers danced to it a lot in the 1990s.

There was even a "sequel" to it, "Force 10 from Navarone" or something like that.

So I imagine, though I've not checked, Google searches nowadays will turn up The Skatalites' rendition (which is not necessarily what you want!).