You replaced the starter and battery on a 1994 Ford Taurus but still just clicks and will not start any ideas?

You may have a loose or corroded ground connection. Not just the battery ground but the engine to chassis ground. You may also have a bad battery cable. If you see swelling on any part of the cable, replace it. Make sure the connections are clean and tight. Did you replace the starter solenoid with the starter, or is it a separate item? If the solenoid is separate from the starter, it is probably bad. It is unlikely that the ignition switch is bad, but possible.