If you have the Ford Chassis Owner Manual, check there for battery replacement guidance. I think you're safe simply disconnecting, changing battery, reconnecting. Used to be the Radio had a Security Code and if you couldn't re-enter it, the radio would no longer work, and anti-theft measure. I don't think that's common anymore.
There's a "memory saver" which is essentially a little 9V battery that you clip to the battery cables before disconnecting. It's supposed to save things like Clock, Radio Stations, and Driving Patterns. But some owner manuals contain specific wording to NOT use one.