No rivets on the lower ball joints in a 4wd. the quickest way to get them out is to use 2 hammers, a large ball peen with the rounded side resting on the top of the ball joint. With the LCA supported by a jackstand, smack the flat side of the ball peen hammer with another BFH. This will keep you from mushrooming the top of the old joint and protect the control arm. The new joint will need to be pressed back into the control arm.