Will this bolt straight to my tailgate where the old light was?

Yes. This mounts at factory tailgate bracket points — no drilling or welding required. You'll be able to reuse existing mounting holes.

Does this come with wiring harness adapters or do I need the OEM connectors?

Wiring hardware is not confirmed with this assembly. Test-fit the connector to your truck's existing tailgate harness before purchase to verify compatibility.

What's the difference between this LED light and a stock incandescent unit?

LED lights produce higher output, use less electrical power, and last significantly longer. The black smoke lens keeps the modern appearance while meeting visibility standards for brake function.