Will this headlight work with my factory wiring harness?

These are designed as direct replacements, so your existing harness should connect without modification. Test the fit and electrical connection before fully securing the assembly.

Do I need to order both sides, or can I just buy the right side?

You can buy just the right side if that's all you need. If you're replacing both headlights, order the left and right separately.

What about the bulb — does it come installed?

Bulb assembly not confirmed — verify your current bulb type before installation so you have the correct replacement on hand.