HELP!.... Interior light won't turn off

[bhans40]

98 Mark....The drivers side rear passenger courtesy light won't shut off .....started yesterday....I pulled the negative cable off to keep from draining the battery....All the other courtesy lights come on and dim when the door is closed except the left rear one it stays on until I pull power.....I've checked the dash light rheostat and turned the interior lights on and off with it....stays on.....I need some help please.... My name is Bruce L. Hansen....Senior Citizen....and I don't suffer fools

 

[sprocket]

Take the bulb out?

 

[capt fast]

pull the assembly out and check the internal switch. jammed or shorted but that is just a guess. not much else form my point of view unless something plastic is melted