AOD doesn't have an electical button for engaging OD. Read up in the Trany tech articles, first page of the "Ford OD Transmissions 101" article, the introduction. Even though it doesn't have much information on the AOD, the single paragraph should contain what you need.
97 Mark VIII LSC/Silver/Gray leather
97 Cougar 4.6 Sport/White Opalescent Tricoat Metallic /Gray leather down but not out?
89 Cougar LS 3.8/Oxford White/Gray velour/HG need replaced AGAIN
00 Grand Marquis LS/Vibrant White/Gray velour
63 Falcon 302/black and rust/shed isn't moving
82 F-150/Oxford White/dumb VV carb doesn't pass emissions