Heat them up with a heat gun (on LOW!) or a hair dryer, then use dental floss (you DO floss, don't you?) behind the sticky stuff to remove the offending reflector. Use a bit of Goo Gone or a wee bit of alcohol to remove any remaining residue. For the silly sticker on the tank, just heat it up a bit & peel it off. Use your finger (no, not that one) to rub off any remaining gick.