Can't answer your question, but can offer a solution/option for you:
https://www.f150gen14.com/forum/threads/builtright-pro-dash-mount-hardwired-12v-and-usb.17703/
The point of locking out gears is to stay out of boost when towing. I don't think you'll get the results you're after. Just let the truck do what it wants.
All Ford is doing here is taking a traditional 60 month loan, extending it to 66 or 75 months and delaying some of the principle payments to reduce the first three years of payment amounts by 15-18%, but you'll end up paying more interest over that time...