I think Ford's liability is preserved if they insist on doing the fuse/harness themselves, with the recall.
If they accepted people doing their own work, that would assume that people could always determine the power wire of the two. If a fuse is located on the sensor wire, then the power is still getting to the sensor, thus a fire is still possible. That harness is their way of insuring that the proper wire is fused.
I personally wish that they would provide a new switch for the actual suspect units. I hope that they have done that, originally the only way that they identified them was by their red top, in the years first recalled. My 99 has the red topped sensor, but it wasn't in the first recall. Now it is in the recall, but that just gets me the free fuse.