There is no way to push it out with a press as Nissan did not provide a support surface. The only way to remove it, is with a 3/4" diamiter 10" long brass rod and a short handle sledge hammer. No need for heat. If you heat they will ooze badly. Place the knuckle over a couple of same hight blocks of wood that allow clearing the floor by the flange side of the stub axle. Wack at it with patience. It will take a while, but it will come out. Read the FSM, that is the recommended (an one and only) way to separate the stub axle from the aluminum knuckle.