i have a little debate going on with my friend. he seems to believe that simple green stains the paint on cars. now i use simple green on the cladding and on the engine and i have not had any problems with it. when i wash the cladding i usually get some simple green on the paint. i have not seen any stain on my paint at all. i read the back of the simple green bottle and it says it is safe for paint. so what do you guys think? i believe it is not harmful to the paint at all.