Vincent,
Do you have any documentation for your vehicle in your library: Service Manual (SM), Parts Manual (PM)?
Having required reference material will greatly help you weed through the, "many posts on other sites," so that you may know what is correct.
Here's a link to an image of the wiring diagram.
https://www.cj3apage.com/index/Tech_Tips/wiring%20diagrams.htmI have hard copies of SM and PM but if you're comfortable with internet searching, Google is your friend. This search was simply, "CJ3A Wiring Diagram."
The book,
The Civilian Jeep Model CJ-3A, by Bob W. has a copy of the CJ-3A wiring diagram in it too (p.23, illust. 3.04) clearly labeling, "Ground Negative Cable," that matches #8 of the wiring diagram in the link I provided.
HTH.