Hi Carl, looking into the door in the top lefthand corner you will see a triangular box ( fords security to stop the door being opened by a slimjim pick) this can be removed by the two large phillips screws in the lock edge of the door one at the top the other near the bottom, it is part of the window channel (keep the window fully up) once this is removed you can gain access to the lock assembly, key and external door handle, sometimes a good spraying with WD40 will cure it but most likely a new lock assembly will be required.
nigel
December 2007