First, you should always list the equipment, like an automatic transmission which would have the starting voltage routed thru the neutral safety switch to the solenoid. If that isn't the problem, the starting circuit wire is red with a blue tracer, common on all domestic Fords. Take the back connector block off of the ignition switch and see if that red-blue wire has continuity to the solenoid (battery disconnected). It may take two people. If there's continuity, it may be the switch.
Jim