Vintage McCarran trivia? A? B? C? ...

I'm trying to recall, just for curiosity, what McCarran was like when I first started visiting Las Vegas (1970s) and how it corresponds to the McCarran of today.

One Big Burning Question is along the line of if (part of) the C gate section is older than the A/B section?

The first I remember being at McCarran was to pick up some of our extended family. I remember the architecture of the terminal (this was back when you, as a non-flying guest, could go to the gates at most airports) as linear and rectangular, not unlike what we know as the C concourse now.

The first time I personally remember flying into McCarran was a couple of years later, probably on TWA but it could have been one of the other "usual suspects" of the time like Untied or American. I remember landing at one of the round concourses, A or B, and thinking "this must be the new section" as it looked to be very new, and clean and bright and modern.

Now today, the A and B round sections appear to me to be REALLY showing their age, and most definitely look to be older than (most of) the C section.

What I'm curious about is what was that older section? Was it the closer-in section of the current C gates? (You know, those first few gates, all on one side, right by where the new security checkpoint empties into the concourse?)

Or maybe was it those few closer in gates of the current A and B concourses?

Or maybe a demolished section that doesn't exist anymore?

I'm guessing that the A section was built in the mid 1970s and the B section very shortly after A.

Anybody know where those gates I'm thinking of were back in the 1970s, and when most of the C concourse was built?

Any ideas?

TIA!

 

History of this airport is fully explained here. Scroll down.
http://www.nycaviation.com/spotting-guides/las/las-general-information

 

I can remember there was nothing south of there except desert, until you got to Henderson, which was a wide spot in the road.

I can't remember the terminal at all. Blotted out by time. I remember that people were walking around in cowboy clothes.