Do I need fasteners to bolt this on, or does hardware come in the box?

Hardware is not included with this mirror. You'll need the factory bolts from your existing mirror or pick up standard hardware at any parts store — mounting points match OEM specs exactly.

Is this mirror ready to install out of the box, or does it need paint?

It ships fully finished in black and ready to bolt on. No sanding, priming, or painting required — you can install it the same day it arrives.

Will this work if my original mirror is power-operated?

This is a manual-adjust mirror only. If your Grand Prix came with power mirrors, you'll need a power-operated replacement instead — they're not interchangeable.