removing sticky backing off paint

[rich19]

i`m putting a small number plate on the front of the ph-quick and was wondering wot the best technique is to remove the sticky backin left. i tried a hairdryer, tar remover scourer pad and i`m not keen wiv hot water as i`ve ruined paint in the past not even near boilin point!

i understand i hav covered most techniques but any ideas wud b welcomed as i do fancy my mini plate

cheers guys and gals