Does this use the factory wiring harness?

Yes. Connector compatibility is designed for OEM electrical points — plug directly into your existing harness with no rewiring.

Will I need any hardware to mount this?

Factory mounting points accept standard fasteners you likely have on hand. Confirm bolt size and thread pitch against your OEM tail light before purchasing fasteners separately.

Is the lens sealed, or do I need to seal it after install?

Assembly method not detailed in product specs — test-fit the lens seat after install to verify seal integrity before hitting the road.