You can hammer them out, they remove downward from the LCA, witha little creative thinking a section of appropriate sized pipe and a piece of steel plate or two they can be installed using a "C" frame press like the free rental tool from Auto Zone.

When pounding the old ones out having the LCA supported by something like a jack stand rather than something softer like wooden blocks makes it easier.

I like Lemforder brand wise, seeing that you are up here in the rust belt you should order new ball joint stud bolts and nuts before you start to have on hand. The bolt is the critical securing fastener between the ball joint's stud and the wheel carrier, it is grade 10 and has a long shoulder. That long shoulder intersects with a cut-out in the ball joint stud to form a positive lock. The old bolt may be very hard to remove and often times is corroded where it intersects the ball joint stud.

Start spraying the fasteners with a penetrant a couple days before attempting the job. Have a propane torch available, 19 mm 6 point serious sockets and wrenchs, a breaker bar and a 4" extension.