Press Enter by John Varley, I believe.
The first story might be “End as a Hero” by Keith Laumer. I read it in the collection Nine by Laumer. There’s a description of the story on this blog, to see if it sounds right:
Interesting sounding story, thanks, but not it. What I read was a more straightforward sci-fi short story (I think), themed more along the lines of the loneliness of space, the isolation of the watch. And as I recall it, it was focused on the mechanics of the deal. I specifically remember the mechanics of quickly and accurately manipulating the keypad that triggers the warning.
“Nightwings”, by Robert Silverberg?
They are on (a post-apocalyptic) Earth, though.
Wow, a life in which the major worry is the inability to remember the titles of three stories sounds pretty good.
James: Welcome to the SDMB (I’m a big fan of your work, but apparently keep getting outvoted at Hugo time).
Your question reminds me of a story called “Oh the Things those Galaxies Say”
Publication: Isaac Asimov's Science Fiction Magazine, November 1980 from 1980 in which an astrophysicist goes to a bar, and is talking with the bartender about having discovered that galaxies are intelligent beings, and that our galaxy is sick (since it has infestations of life inside it). Hence almost all the other galaxies are fleeing it in revulsion - except for Andromeda, who is coming to help (i.e. help by wiping out life in the Milky Way).
Second one reminds me of “More than the Sum of His Parts” by Joe Haldeman, reprinted here More Than the Sum of His Parts - Lightspeed Magazine
I see the similarities, and am actually looking forward to read the full story you posted, but sadly, that’s not it. The “body swap” story was set more in a just slightly ahead of present-day type situation, and I don’t recall the new body to be anything but organic, possibly with some exotic materials, but no robotics. And the main character was just some schmoe on earth who more or less stumbled into the situation.
Ok. I’ll keep looking.
The first one sound a lot, but not totally, like “Panic Button” by Eric Frank Russell. Here’s covers where it appeared in case one jogs any brain cells.
Sorry, no.
Eric Frank Russell’s Panic Button features two exploring aliens who happen across a lone Terran on an otherwise uninhabited planet. Upon finding him, the human pushes a blue button, which frightens off the aliens.
The story I’m remembering doesn’t involve any interaction with the aliens. Just observation of their ships passing the outpost.
I did acknowledge the differences but thought there were enough similairites to warrant tossing it out there.
The way it often goes is that a wrong suggestion reminds someone else of the right answer.
I’m going to throw this out (since my other query was identified earlier - Surface Tension):
It’s probably a YA book or novella. The protagonist is a dentist, who is (possibly) kidnapped in his office and forced to treat an alien who has damaged teeth. The basic damage is obvious, and he completes the tooth repair (I think with gold caps rather than amalgam). But there is apparent a problem with the repair that makes the aliens upset. He finally figures out that the plastic rods that the aliens chew and pass around are a communications mechanism, and the flat even tooth surfaces of the repair need to have specific angles and indentations on each tooth to allow correct use. By comparison with another crewmember, the repair is completed to the aliens satisfaction. The dentist then decides to try his luck in space, and has further adventures repairing teeth around the galaxy …
Prostho Plus?
Yeah. Piers Anthony’s Protho Plus.
And again, thanks. Don’t think that I wasn’t grateful for the suggestion. I’m actually adding all the incorrect books to my list of things to read. I was just trying to highlight what was off about the suggestion in order hopefully put some further bounds out there.
No offense taken. But sometimes folks (myself included) might conflate elements from more than one story.
Thanks - been bugging me since the late 70’s
I never really got into Piers Anthony otherwise …
Back in the mid-seventies, when I was 12 or so, I migrated up to start reading novels that were written for adults. A lot of spy novels, and even trashy novels like “Wheels” and “Hotel” by Arthur Hailey, because I was interested in adult things, mostly screwing and drinking and the like. I never got into SF. Except I remember I checked out a book of such stories and only remember a few details of one of them. As I remember, it involved a group of people going to one of Saturn’s moons to set up a farming colony. I’m not sure if I even finished it, given at the time I thought it was all a bit silly. What could I learn about meeting girls from it? 
But I think it would be fun to go back and try it again, if it can be identified.