Will these brackets fit my existing engine mounts or do I need to drill new holes?

These mount at factory points — no drilling needed. Your original bolt locations will line up with the bracket holes. Just verify your specific engine's mounting configuration before final assembly.

Does the polished aluminum need any prep work before installation?

The finish comes ready to install. If you're painting or powder-coating your engine bay, you can either mask these brackets or remove them temporarily. The polished surface doesn't require sanding or priming on its own.

What hardware do I need to bolt these down?

Fastener specifications depend on your vehicle's service manual and mounting configuration. Bring the bracket set to your local shop or cross-reference your engine's original bolt pattern — most small-block installs use standard automotive fasteners you probably already have.