Will this interfere with my tonneau cover or bed cover?

The spoiler molding is designed to sit on the tailgate itself, not extend into the bed. Most tonneau covers install above the tailgate and won't conflict, but measure your specific cover's coverage before committing to install.

Does this require drilling, or does it use factory mounting points?

This uses factory mounting points on the tailgate—no drilling necessary. Fastens with existing holes, making install straightforward with hand tools.

What do I need to do to prepare it for paint?

The surface is primer-ready, so light cleaning and a standard automotive primer will bring it ready for basecoat and clear. Follow standard finishing practices for your paint system.