This worked. It probably would not have been necessary if I'd removed the glow plug! I guess if one bought the tool and legitimately could not get the prechamber removed after one attempt, then I'd epoxy since the tool is probably damaged too at this point.

Getting older and I am clearly going to have to become super methodical with notes. Did a test removal on older car and took the plug out first. Thought I'd done so on this car. In my defense the glow plug wire was attached with a much smaller nut (nut built into harness missing). I am still shaking my head on this.

Didn't notice the glow plug issue until I had the intake manifold off. Replacing shutoff valve today and putting back together. May the maker help me from another Mr. Magoo foul up.

Car is up and running. Prechamber pull and replacement has been a success. Now, I've got to return bunch of parts for the aborted head gasket replacement.

X2 on the getting Old issues.
It seems like all the things I do these days are much harder then they used to be.
Some of the issues are Physical; lack of strength and dextarity and some Mental; especially when it comes to remembering things.

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84 300D, 82 Volvo 244Gl Diesel

I seem to remain as systematic as ever so farat 70. Just slower to initialize and get a job wrapped up. Twenty years ago if a load of parts came in for one of my cars chances are they would be installed in the next twenty four hours. Now I may not even get to it for a week or so. Results in an almost continuous line up of things to be done.