Do these lights plug straight into the factory holes, or do I need to drill?

They mount at factory points — no drilling required. The bezel sits into the OEM opening and fastens with existing hardware locations.

Is wiring harness included, or do I need to run my own?

The switch assembly is included, but full harness routing depends on your truck's current wiring. You'll likely need to tap into power and ground at the battery or fuse box — standard DIY job with a multimeter and basic hand tools.

Can I return these if they don't fit?

These are designed for your specific model and mount at factory points, so fit is solid. Review the product images and compare bezel shape to your bumper before purchase to confirm compatibility with your truck's condition.