Was replacing the power steering high pressure line and bleeding the fluid. While steering L to R heard a pop turing to R side. Found this.
Looking at it again its definitely the idler arm stud. Have someone turn thw wheel back and forth and look under there and see what it does
That castle but is still held with the cotter pin where it was installed originally, it's definitely the stud pulling out of its anchor point. So whichever part the stud side is on - the link? Good luck extracting it, hopefully it doesn't rip out entirely from the link. Use a jaw puller, not a pickle fork.
To me it looks like the boot has scooted up, but other than that it doesn't look like anything is wrong. I get a pop when I turn my wheel all the way to the right because the Idler arm hits the end of my steering dampener.
At least it didn't do it while driving it! Last year a friend of mine pulled into a parking spot outside our building with his old 82 2wd pickup. As he made the turn into the space his pitman arm stud popped out of the casting and he was without steering, he got lucky I suppose since it didn't happen on the road. Helped him with a parking lot fix using a ratchet strap and some bailing wire - enough for him to move a few hundred feet to where he could work on it without being hassled by parking enforcement.