Tar-spreading scene: The guy Ennis is working with reminds Ennis in a negative way of Jack (he's neither cute nor fun), and also of how Ennis himself could very well wind up in 20 years. Ennis is wearing a blue plaid shirt (Jack's colors). The big clue is the other guy says something like "the wife said I would break my back working blah blah blah" and it's those words that trigger Ennis to stand up and look wistfully off to one side into the distance, as he always does when thinking of Jack.
Oh, they are spreading (hot) asphalt, which is a mixture of pitch (contains a petroleum based black tar) sand, and fine gravel. They are putting an asphalt surface on a dirt road. I have worked for the county highway department and we did patch pot-holes in the roads which had an asphalt surface. I looked at the scene in the movie and they are putting that directly on top of dirt without the roadbed even being properly prepared with a layer of coarse gravel. In the movie, Ennis works on the highway crew BEFORE he moves to Riverton; but, in the AP story, AFTER he moves to Riverton, he has a full-time job with the highway crew and works on a ranch on the weekends to pay for keeping his horses there.
Oh, I think that one of the reasons that Ennis looks to the side while the other guy is yakkin' is that he is wishing that he was somewhere else and did not have to listen to the guy. I have met guys who will talk to anyone who has ears whether the other person wants to listen or not.
Drive-in scene: The woman in the movie is emerging from a trailer, a reminder of Aguirre's trailer. There was some talk of what the actual movie is onscreen, which I missed, though I think that may be significant, too. (Starboardlight, if you read this, weren't you in on that discussion?) And Alma grabs Ennis' hand and presses it to her pregnant belly in a way reminiscent of Jack's grabbing Ennis' hand in TS1.
Well, it is like this, that ain't in the book, the drive-in movie scene, that is. I have known women who got married just so they could have babies and they did want their husbands to put their hands on ther tummies. As far as the reason the scene was added to the story, one will have to ask those who were involved with the making of the movie.
In the book, there is absolutely nothing really romantic in the relationship of Ennis and Alma.
Quote from the book which has some details about the birth of Alma Jr.
In December Ennis married Alma Beers and had her pregnant by mid-January. He picked up a few short-lived ranch jobs, then settled in as a wrangler on the old Elwood Hi-Top place north of Lost Cabin in Washakie County. He was still working there in September when Alma Jr., as he called his daughter, was born and their bedroom was full of the smell of old blood and milk and baby shit, and the sounds were of squalling and sucking and Alma's sleepy groans, all reassuring of fecundity and life's continuance to one who worked with livestock.
That "all reassuring of fecundity and life's continuance to one who worked with livestock" makes me think that Ennis's attitude toward the situation was he and Alma might have as well have been keeping house in a barn. And the birth of a baby girl was, to Ennis, like the birth of a filly to a mare. We do know (according to the book) that Ennis called his horses and his daughters "little darlin'." He must have just called Alma, "Alma."
