GEM module question

I've been having problems with my power locks working, they don't unlock with the buttons on the doors, only with the remote, and the courtesy lights under the outside mirrors will stay on for several hours after closing the doors with the engine off. As I understand it, these are controlled by the GEM unit. My question is, if I replace the GEM, does it have to be programmed by the dealer? Or can I just pop a new one right in? '99 Explorer XLT, 4wd auto,4.0 pushrod V6 Thanx