You would have needed a friend if stealing an F-4 though, since
someone had to do the switches on the INS in the back seat to get an
alignment. No nav and no expensive flight instruments without it.
Ditto no ability to run the radar. Also you might want to know a bit
about securing the rear cockpit straps, etc. or you could find the
stick jammed from belts, harnesses, buckles and shifting seat kits.

The Collings Foundation F4D (which I have worked on) has a GPS installed in
the front cockpit. You would still need some help with the ground
equipment for startup.