Do these mount at the factory rocker points or do I need to drill?

These use factory mounting locations — no drilling required. You'll use existing holes and fastening points on your extended cab.

Will the chrome finish scratch easily, or can I touch it up myself?

Chrome is durable but can show scratches from parking lot contact — that's where the honeycomb panel takes the impact for you. Minor scuffs on the finish can be addressed with chrome polish; deeper damage would require refinishing at a shop.

Do I need to remove the old steps first, or can these install over them?

Your truck doesn't ship with factory steps in this location. Install prep depends on your current setup — test-fit before committing to your mounting method.