If my truck has rear sensors, can I still use this cover?

This cover has no sensor cutout, so you'll need to either disable the sensor system or route wiring differently. If your truck came with factory rear sensors, plan for that modification before install.

Do I need to remove my factory bumper frame to swap this on?

No — this is a fascia cover only. Your existing bumper frame, reinforcement bar, and hardware stay in place. You're only replacing the outer cover panel.

Does this come primed and ready to paint?

Mounting method and finish condition not specified — confirm with your supplier before ordering if you need primer or raw material. Have your paint shop inspect fitment before committing to a paint job.