Best way to remove surface rust on sandblasted sheet metal

All I was saying was this old car metal we are dealing with here is what 40-45 yr old. Seems like it can rust from the inside usually and is therefore thinner. Sand blasting makes it thinner yet no doubt. . Maybe his fenders were not blasted with sand, I forget.
I had a guy way back in th 80's that blasted with sand and was a master. He talked me in to letting him do a 68 roadrunner hood. HE did not worp it one bit, but he was a master. He had a boon truck and would raise my cars up by one end, lay under it on his back and blast, then do the other end!! I never heard a man cuss like him either! Made me even blush.