Do these use factory bolt holes or do I need to drill the bumper?

These mount at factory fog light locations — no drilling required. Your Tundra already has the mounting points ready to go.

Does the switch wire into the factory switch panel or mount separately?

The included switch is independent and mounts separately. You'll run the harness through your engine bay and decide where to place the switch for easiest reach — typically under the dash on the left side.

Will these work if my bumper has been damaged or modified?

These are designed for factory bumper cutouts. If your bumper is aftermarket, cracked, or heavily modified, test-fit before finalizing installation to confirm clearance and mounting alignment.