ok well recently we purchased a second Camaro in Oregon for a good price, straight body, but needed paint and a new interior. Well when we started sanding it down to get rid of some surface rust in some rock chips and prep for paint we have noticed that there appears to be rust under the paint, even though the paint isnt bubbling. Can anybody tell me what is going on here?

 

Doing the usual thing where the rust can branch out under the paint. Get the whole car stripped down to bare metal and repaint.