John, there was a big drop in quality in terms of rust when Mercedes switched from acrylic paints to water-soluble paints in 1993. .
They introduced galvanised chassis from 86 onwards for most cars and even the bulkheads on post 86 107 SL's are renown for rusting badly. The paint was so soft post 93 if you didn't remove bird droppings immediately it burnt the paint. Oh those were the days.
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