Surface rust question and help please?
 

Rust question from a newbie with bodywork. I have always had mustangs so no surface rust on them. I am doing a 69 Nova with surface rust inside the car on the roof and some rust on the metal panels inside, but it's just surface rust. My question is do I strip it down to bare metal or put a rust type inhibitor on the rust or what? Not sure how much work to do to it trying to get it off?