I just knew there was a thread about removing sticky nonsense... Quoting Mica:
You can use mineral oil or lemon oil to dissolve lots of adhesives. Like has been suggested, if you can get an edge started, then swab the oil in the exposed area and continue to peel the sticker away.
Once you get the whole thing off, you can clean up the sticky residue on the bass with an acetone-soaked wipe. You can use acetone to remove the sticker, but it's hard to controle the placement and evaporates quickly.
en welkom, natuurlijk!