Do these come with installation hardware and wiring harnesses?

The set includes the eight headlight units only. Mounting hardware and electrical connectors are not included — you'll need to source those separately based on your vehicle's factory attachment points and wiring configuration.

Can I install these myself, or do I need a professional?

Installation depends on your vehicle's headlight design. Some vehicles allow straightforward bolt-on replacement; others require partial bumper or trim removal. Check your service manual or consult your vehicle's forum community for specific steps before ordering.

Will the black housing show swirl marks or need protective coating after installation?

The black finish is factory-applied and ready to use. Over time, exposure to UV and road conditions will age any headlight housing. Protective coatings like clear bra or UV sealants can extend appearance, but they are optional and not included.