@Literati914 Lots more to ball joint design than that.
I don't know the specifics of Lemforder specs's but consider these:
Articulation angles need to be accomodated
The ball joint liner material has a huge impact on joint friction, noise, and life
Ball size vs. loads
Roll forming the end cap on to have approprate pre-load on the ball joint
Heat treat
Ball plated vs. polished
Ball roundness
Durability & life cycle prove out. Really bad things happen when tie rods aren't connected to knuckles.
I've never done ball joint design from scratch but worked with those that have. I don't want that job!
Seems like a simple purchased commodity but they aren't.