Excuse my fine photoshop skills, I outlined in some pics a badly rusted fiero.
The area between the red lines are the Frame rails, if you have rust here, thats real bad, and not safe once these parts start rusting away. The yellow circled area are sheet metal thats gone, still bad, but not a safety issue.
The 2nd picture is from the inside, the red outline shows where big parts of the frame rails are rusted away, yellow is sheet metal work thats gone.
The 3rd one shows how much of the frame rail is gone from the outside.
It is not finacially practicle to repair any rust when it gets to this point, usually the amount of work needed becomes big $$. It's cheaper to find a rust free fiero and start from there.
You can repair this amount of rust and still make it safe, but It requires a LOT of work, Again, not worth the effort.
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