trevanian said:
you'll realize there is no way they could have done a chestpiece that looks even vaguely realistic.
Not to mention that whenever members of my old ST club pitched the question to women (and some men) who'd actually been on the set when Montalban had been in costume for ST II, we always got the same answer. Bjo Trimble, Susan Sackett and others always swooned, "Oh yeah, that was his real chest!"
Judson Scott and Walter Koenig gave similar answers, but without the swooning. (Not so sure about the swooning level of George Takei's answer now, though.)