Go to your Ford garage and they might repair it for you under warrenty. It may be out of the paint warrenty but not sure, cant remember if its 6, 8 or 12 years.

My 1st Focus, also a 1999 T, had rust under the rear doors & boot where it was sealed. Ford repaired that under warrenty as it was a common problem with them. That was about 3 or 4 years ago.

They also go underneath the wing mirrors and on the boot if you have a chrome boot strip.

Andy