Can you replace the wss itself? Or do you just change the connector and/or harness?

Hello, what is a "wss"? Do you mean a vehicle speed sensor, VSS? If so, yes, you can. If you need guidance and assistance with this task, I would recommend seeking help from a local technician near you. https://repairpal.com/repair-shops/lincoln-repair-and-service-in-homestead-florida