I came across this on a Jeep Wrangler forum for renewing black/grey trim like fenders, bumpers, etc. that are unpainted plastic. I've usually use chemical products like #38 but there they use a heat gun to heat up the plastic and it returns its new shiny look. Of course you would have to shield or remove items that melt easy like turn signal lenses, tail lights, etc. Has anyone tried this on their car?