Similar to trialswarrior advise...peel back the lifted decal a little further, wipe underside of decal and fender clean with alcohol, heat decal with hair dryer enough to make existing adhesive tacky, spray some 3M spray adhesive to your fingertip (wear latex or nitrile gloves), dab a thin layer of adhesive to both decal and fender, wait 10 seconds or so, press down and hold 10 more seconds. After heating the decal, don't wait to apply the adhesive....you want the decal to be pretty warm, but not hot or it wont adhere. If it's cold outside, apply warm heat to fender as well. Clean any excess adhesive off with goof-off. May take a few tries to perfect it, but ends up holding better than factory application.
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