Do these mount to the factory roof rack or directly to the roof?

These mount at factory roof rack attachment points — no drilling required. Test-fit before committing to the final fastener type, as mounting hardware may vary by installation method.

Will these fit with aftermarket roof baskets or cargo carriers?

These are side rails and won't obstruct most roof baskets, but verify clearance with your specific carrier before purchase. Roof rack geometry can differ between trim levels.

Do I need to paint or prep the black finish before installing?

The black finish is ready to install as-is. No primer or paint prep needed — bolt them on and you're done.