Depending on local labor rates count on $700-$800. It is a just about an all day job.You must remove the entire dash carrier to do this.
Step by step directions if I wanted to replace heater core myself on a 2002 Ford Taurus
Print this on first viewing, it might time out as it is long.
NOTE: Lift upwards on the rear edge of the defroster grille then slide rearward to remove.
Vehicles with EATC
CAUTION: Do not attempt to bend any part of the supplemental temperature blend door lever.