PCM is a 10 minute job, if that. I think there is a How To on installing a Superchip that tells you everything you need to know with pictures. One bolt under the dash for the bracket, one bolt behind the Power Steering resevior (top left of engine compartment if standing at the front bumper - have to lift the resevoir out of the way) for the harness connector and it's out. If you DIY, be careful not to bend any pins when putting the connector back on.
Unfortunately, you'll need to have two keys programmed when you replace the PCM. That might be baked into the dealer's cost quote to you. But there is some money to be saved by buying a PCM from Bill Jenkins or Ford Parts Online and putting it in yourself. The tough part will be getting the car to Ford for the keys (got AAA?).