My '60 Volkswagen Beetle uses a number of electrical components that are equipped with round screw terminals, like you can see in the picture below:
What is the most ideal wire termination for these type of terminals?
So far, I've been considering the followings options:
Soldering the end of the wire
Although it will keep the wires from fraying, it takes a lot of practice to deliver a consistent job each and every time. Also, soldering inside a car is far from ideal, especially in awkward spaces. Wire terminations are also almost never soldered in aircraft and motorsport applications, same goes for automotive manufacturers. Must be a good reason for that.
Crimping ferrule onto the wire
This seems like a good option and I believe the VW factory did this. However, the tools they used made a rather small indentation which doesn't seem very reliable to me. I can find proper crimping tools that make a square or hexagonal compression, but I worry about the contact area and possible resistance with these ferrules in those round screw terminals. Is this something to be concerned about?
Soldering ferrule onto the wire
This leaves the round shape of the ferrule intact, but, as said, there are many reasons not to prefer soldering for automotive applications.
Are there better options out there?