I purchased this very grubby stained showroom cover on eBay the other day to cover my car whilst in the garage. Looking for advice on how to clean before I use it. Apart from normal household detergents and cleaning product has anyone got any experience on other products to maybe pre soak etc. The stains look a bit oily some old paint splashed (which are picking off to reveal a brighter yellow underneath) and generally i would think 30 years of grime and dust.