Do I need to seal or treat the aluminum before install?

The polished finish is ready to bolt in as-is. If you're concerned about corrosion over time or plan to store the car long-term, a light coat of clear protectant on the exterior won't hurt, but it's not required for function.

Will the level sender work with my existing fuel gauge?

The sender is a standard float-type unit. It'll work with any OEM or aftermarket gauge designed for a standard fuel tank sender—no special wiring. If you're swapping into a different vehicle, confirm your gauge accepts a sender before committing.

What mounting hardware do I need?

Mounting brackets and fasteners are not included with this tank. You'll need to source or fabricate straps and bolts suited to your installation location. Test-fit the tank in your planned position first, then measure for bracket placement.