Do I need to run new wiring through the firewall?

The harness is pre-routed and designed to connect at factory points. You'll need to confirm the wiring runs cleanly to your battery and fuse box; some trimming of existing clips may be needed depending on your specific setup.

Will these install into the factory fog light openings?

Yes. These are designed to fit the factory fog light cutouts on the model listed. Test-fit before fastening to ensure proper alignment, then secure using OEM or equivalent hardware.

Are the bulbs replaceable, or are they sealed in?

H11 bulbs are a standard automotive size and fully replaceable. You can swap them out when needed without disassembling the entire light housing.