If posssible of course use a heat gun to heat up and soften glue and then when removed use mineral spirits or a little thinner on a rag to whipe remaining sticky stuff off. My suggestion if available use a electric buffer/pollisher and buff car out or atleast around area where emblems where to blend in color difference if any where badges were.might be able to get away with just hand waxing out if paint is still good shape on car.