The lock cylinder was set for the ignition key of the original car IIRC. You would need to either a) get the cylinder tumblers redone for your key, or b) get a key made for the current tumbler setup. Either way, it's a locksmith job (or Ford if you like).
Anyone disagree? Or did the early Contours come with a "Valet" key (PATS wouldn't have been an issue).