Do I need to drill the roof to mount these?

Depends on your vehicle's roof design. Test-fit the lights on your roof line first — some vehicles have natural mounting points or pre-drilled locations. If drilling is needed, use a hole saw appropriate for your roof material and seal the holes with automotive sealant afterward.

Will these lights work with my truck's factory wiring harness?

These come with their own wiring and rocker switch, so they're independent of factory systems. You can hardwire them to a dedicated fuse or use existing auxiliary circuits if available — check your vehicle's electrical schematic to confirm available amperage.

Can I replace just one light if a bulb burns out?

H3 bulbs are replaceable and widely available. When one burns, pop out the old bulb and swap in a new H3 — no need to buy a whole new assembly. Keep spares on hand if you run these lights frequently.