FWIW, the Haynes manual is almost useless. So I watched a video and it showed a snap ring for the lower one. However, mine has no snap ring. It is a press fit with a flare, or flange, in the top. I peened the edges up and was able to hammer it out then.

 

FWIW, I don't have a ball joint press kit. To install the lower, I raised the truck off the jack stand using a piece of tubing, axis vertical, on a jack. The tubing I used is the almost the same diameter as the flat on the lower part of the body of the ball joint assembly. In effect, I used the weight of the truck to create the same direction of force a press would. When I then hit the lower A arm with a 4 lb mallet the impact slowly drove the ball joint into the A arm. Worked for me.

 

the factory ball joints have the flair on them, if the video showed removing a snap ring then they were replacing a aftermarket one.