Goo-b-gone. a few drops, let soak and patiently work the decal off with a soft cloth. Hasn't harmed any hard finished surfaces in my house.

Thanks for all these suggestions guys.  And I have posed the question to Mica as well.  Cheers.

Looking closer, I can't tell is if the decal is  mylar or a similar material. If so, you'll need to lift an edge and apply the solvent directly underneath to access the adheasive, then work your way around the decal as it loosens.
 
Good luck with the sale, it's  a beautiful bass.

Yeah, the sticker is one of those vinyl ones.  Thanks for the info.

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 comtrole the placement and evaporates quickly.

Thanks guys for all of the responses.  One last survey before the sticker goes.  Would you guys keep it or get rid of it (although I think I already know the answer here  Also, what about the signature?  Does it stay or go?

Regarding the signature, that's a call only you can make. Autographs typically have only value to a particular and small segment of people.  
 
From personal experience, as a seller I wouldn't let the possibility of a few extra bills in my pocket spoil a deal with someone that doesn't care who signed it. I'd leave it on and let the buyer decide it means to them.
 
IIRC, you didn't know whose signature it was? It's hard to make out from the pics.