Do these mount at the factory bumper points without drilling?

Yes. These are designed for OEM mounting locations — no holes to drill or brackets to fabricate. Test-fit before final fastening to confirm alignment with your bumper panel.

Will the bulbs stay lit if I install these?

These are marker light housings with smoke-tinted lenses. The bulb function depends on your wiring harness — if your stock markers work now, these will work the same way once mounted. Bring your existing bulbs with you during install.

What should I do before I bolt these on?

Clean the mounting surfaces on your bumper and inspect the back of each housing for any debris. The lens is finished and ready to go — no prep work needed on your end.