These are so good to see, thank you. The top one definitely is Vietnam era, you can tell by the red stars on the intake.
For a real look at the plane and the guys who were with it, click
here. Such a piece of history right there. I really want to knock up a plastic kitset of a Vietnam era Phantom some day.
The bottom is late 80s generation, Spangdahlem, Germany. Lo-vis markings were a give away for 80s pretty much anyway
The middle one I can't find anything for. They are all wearing quite modern Aim-9L Sidewinders, even the first one. So can't judge the age by the equipment she carries
(all that stuff above thanks to Google, I'm no Phantom expert!)