The screw in insert worked great, with a properly made tensioner lever! Here is the source of the exact item for anyone looking in the future:
https://www.amazon.com/dp/B0CH8JKNP6
I did have to shave just a thread off the end to make it fit properly before it got too hard to turn in. Your results may vary. I also did put semi-permanent loctite on it on the final screw in.
The new axle went it well, and new axle seal seated without leaks so far. All timing was updated to the later wider style and components and now, so long as she makes it, the time won’t need to be touched until 350,000 miles.
I ran into so many issues throughout this whole project that I’ve decided to delay the radiator replacement and PCV servicing but, that’s next on the list someday soon...
Hope it helps people and thanks for tips and advice I received...