Will this bolt in without any modification to my Pilot?

Yes—this assembly mounts at factory points using OEM bracket locations. No drilling, cutting, or adapters needed. Bolt it in and you're done.

Does the bulb come installed or separate?

The assembly ships without the bulb cartridge. You'll need to source a compatible H11 or 9006 bulb (depending on low/high beam configuration) and insert it before installation. Check your owner's manual or the factory part number on the housing to confirm the correct bulb type.

Can I return this if it doesn't fit?

Test-fit the assembly on your vehicle before finalizing installation. If the mounting brackets or connector don't align, contact support with photos—fitment issues are rare on OE-spec housings, but they can happen if your vehicle has prior collision damage or non-factory parts installed.