Do I need to run new wiring for the switch, or does it tap into existing circuits?

The switch is designed for direct integration into your Yukon's electrical system. Exact routing and circuit connection depend on your vehicle's wiring harness — review the installation guide that ships with the kit or consult your service manual to confirm wire locations and gauge.

Will these mount at the factory fog light points, or do I need to drill?

These mount at factory locations with no drilling required. Your Yukon has pre-drilled mounting points — the assembly bolts directly into place.

Are the lenses sealed, or do they fog up over time?

Clear lenses are sealed against moisture and road spray. Standard maintenance — occasional cleaning with water and mild soap — keeps them clear. If condensation appears inside the lens housing, it typically indicates a breached seal, which would require lens replacement.