An update to close this out....
Finding the magic words to ID the failed part for this starter was very annoying. The Internet is a dumpster fire of mis-aligned SEO (*) and YouTube shaky clickbait videos with 12 mintes of "Blair Witch Garage" nausea-inducing video with maybe a 3-second mention of what is the actual information. I finally found my specific problem, but all the guy did was replace the starter (followed by 30 seconds of him driving to prove the noise was gone, thanks Ford guy!)
Now, I could buy just a new starter solenoid. O'R____y's has one. But whether it includes the plunger return spring is like:
MYSTERIOUS
Also, since I have needed to drive my truck to work, and don't have a wife/manservant/chauffer, I have been unable to leave the truck (or just the starter, it comes off and on in 2 minutes) at any of the several starter rebuild places near work. I don't speak enough Spanish to find out how long the surly, very busy, and maybe suspicious guy at the starter place(s) will need to keep it. And of course explaining exactly what is the problem and does he have like 100 of these springs lying around and could maybe he replace it in 15 minutes, while I throw a few 20's at him, is impossible.
Nooo... you got to bring it in, the starter, I bench test it, I dunno.""
So what this means is, I am buying a new starter for $150 from P___'s Starter & Alternator.
Then I can take mine apart and confirm that it is the:
Part No. 1940974 — Part SPRING - RETURN
www.delcoremy.com
_OR_
Part No. 1958679 — Part PLUNGER RETURN - 40 NEWTONS (8.99 LB.)
www.delcoremy.com
I seem to also need a bushing or bearing and a retaining ring for the starter shaft at the nose cone. I expect the pinion gear (or RING gear, or maybe BENDIX gear) is ground down like my patience and faith in humanity and hope that we won't forget EVERYTHING we have ever invented as a species.
Now P____ was pretty surly, and also suspicious. So I think I will be buying a mini-style starter. I THINK. All I know is it is in stock, and I will ask for staggered bolt pattern. Hopefully this will not have some metric/SAE bolt mismatch, considering I am asking for a direct replacement it had jolly well better be.
At least getting a mini-starter will be good because I need to install my BITCHIN' HEADERS as soon as possible.
Thanks for the advice so far. I'll report back maybe.
BRetty
PS -- Search tags so people can find this post if they have this problem:
starter solenoid plunger return spring pinion gear loose
* -- Searching for "delco remy starter solenoid plunger return spring", the 12th hit was the California Secretary of State's office at 300 Spring St. I could have watched hours of video about lawnmowers and snowmobiles and boats. Aaaaarrrggghhhh.