Use a fishing line, and going behind the emblem move it side to side, in a saw-ing motion, in order to detach it from the adhesive. Do not put too much pressure on the line and be careful not to scratch the paint.
Spray some WD-40 or GooGone onto the glue that is left over after removing the emblem. Let it soak for about 5 minutes. Use a credit card or a drivers license and carefully scrape the residue. Use medium pressure and avoid scratching the paint.
Line up the emblem, peel the protective sheet from the adhesive and press on the emblem evenly starting with the middle, working your way to the edges, to ensure a strong bond.