Do these mount at the same points as the factory tail lights?

Yes. These use factory rocker points — no drilling or custom brackets needed. Disconnect the OEM harness, unbolt, and swap them in.

Are the red bulbs sealed inside or can I replace them later?

The bulbs are included and installed. If you need to swap them down the road, you'll have access to change them; exact removal method depends on the assembly design.

Will these work with my truck's existing wiring?

These are designed as direct replacements, so they plug into the factory tail light harness. If your wiring is original and functional, no rewiring is needed.