Porsche used the pinch joint ball joint from 1969-1972 on 911's and 914's. They abandoned this design is favor of the taper pin type that was used until 1989 in 911's.
Here is an example of what can happen to these struts as the ball joint pin can wallow out the strut. I do not know the history on this set as I found them when looking for a good pair. The late Cap'n Krusty (John Larson) told he he changed out dozens of these ball joints and struts due to the weak design in the early 70's.
To get away from the early struts on a 914 you need to change struts, rotors, calipers, brake pads, brake backing shields, flex and hard lines.
I you are restoring an early car check your struts. I have also seen the threads for the pinch bolt strip in the housing and a bolt and nut are used.

As per our conversation at the swap meet I'm moving forward with trying two different trains of thought.

1. Figure out why Porsche couldn't get this to work when quite a few other manufacturers have been using them for decades.

2. Is it possible to save undamaged units and convert them to the wedge style bolt?

After ordering a brand new ball joint from Pelican and installing it my first observation is that Porsche used the wrong size bolt. The factory shouldered 10mm bolt does not come into contact with the ball joint.

I need to do some final measurements but I believe the solution maybe as easy as a drilling and tapping 11mm or 7/16-20 bolt or drilling all the way through to be able to use a lock nut on the back to prevent loosening. Doing this would load the ball joint tightly into the housing just like the later wedge bolt does.

I'll need to figure out how to bench test it to be sure.

Or if the struts are in good shape, just install them properly and keep on using them. They don’t automatically go bad. There are still thousands of cars with them on the road.

I agree with you on that. But they are known to come loose under hard use so I want to make sure I don't have any issues down the road.

I had Tangerine Racing modify my 911 pinch bolt struts to later wedge style. I sent him the bottom couple of inches of two 914 strut cans. wedge style. The strut cans are the same. He was raising the spindles for me and this was a easy choice.

There are so many things that loosen and break on cars. Some you can anticipate, some you can't.

Don't I know it lol