92 Taurus Door Chime

This week I purchased a 92 Taurus. The chime sounds whenever the driver door is open. I am the 3rd owner. The fellow I bought it from says it's always been that way. I don't think it should be. There's a little switch in the ignition key/lock mechanism that closes when the key is inserted. The switch is normally-open (key removed). I took the mechanism out and examined it. It's working properly (it is not stuck closed). As far as I know, there's only two things that should sound the chime, exiting with the head lights on and/or exiting with the key in the ignition switch.
I believe that most of these normally-open switches close and provide continuity to electrical chassis ground. Am I correct?
Is there wiring diagrams available that will show me where and which wires I can probe to see if they are shorted to chassis ground?
Thanks for your help.

fiddle with the ignition cylinder in the steering column. every ford over five years does this. it gets loose inside there, and sets the chime off.

find the power to the chime and cut it. i hate door chimes. i wish they would commit mass-suicide.