Do I need the right cover too, or does this work as a standalone replacement?

This is the left panel only. If your right side is damaged, you'll want to order that separately. If only one side needs replacing, this cover works on its own—no fitment issues.

Will this bolt straight to my truck, or do I need to modify anything?

Bolts to factory mounting points with no modifications. You'll likely reuse your existing hardware if it's in good shape—just verify bolt condition before install.

Can I paint this before installing it, or should I wait?

Paint before install if you want a clean finish without masking tape lines on the truck. The panel arrives unpainted and ready to accept primer and color, so you have flexibility either way.