PM todras to get a Ford CD.
http://www.contour.org/ubbthreads/showprofile.php?Cat=&User=1049&Number=1282832&Board=trouble&what=showflat&page=&view=&sb=5&o=&fpart=1&vc=1
What are you going to do if you change the ignition switch and it does not fix the problem? If everything points towards that, then yes, but at this point you are just shooting in the dark.
Actually, if it were me, I would just disconnect the wiring to the light on the door switches and see if the problem is gone (Try Fuse 34 for courtesy lights). Better to not be able to see the door lock lights than have a dead battery.
Also check the Central Timer on the Passenger Compartment Fuse box under dash, left of steering column.
http://www.contour.org/ubbthreads/showflat.php?Cat=&Board=trouble&Number=1051299&Forum=trouble&Words=central%20timer&Match=Entire%20Phrase&Searchpage=0&Limit=25&Old=1year&Main=1050786&Search=true#Post1051299
Central Timer location, 2nd picture, retangular looking box on Fuse Box, right of his left thumb.
http://www.contour.org/ubbthreads/showflat.php?Cat=&Board=trouble&Number=1056473&fpart=1&PHPSESSID=
Fuse diagram
http://www.contour.org/ubbthreads/showflat.php?Cat=&Board=trouble&Number=887004&Forum=trouble&Words=brake%20lights%20fuse&Match=And&Searchpage=0&Limit=25&Old=6months&Main=886893&Search=true#Post887004
