Will this work with my existing rear sensors?

Yes — the sensor holes are pre-drilled to match factory sensor locations. Your existing sensors should thread through without modification.

What fasteners do I need to bolt this on?

Mounting hardware is not included with the step pad. You'll need bolts that match your truck's factory bumper attachment points — check your service manual or existing hardware for the correct size and spec.

Does this need primer or paint before installation?

The step pad ships unfinished. Apply primer and paint before install if you want a finished look, or install as-is if you're covering it or prefer bare material.