Cels Forum

The best way to remove a sticker from anything is by 
applying indirect heat, by using a hairdryer on a low
setting at a great enough distance from the item that it
will only raise the temperature a few degrees (4 -6"), so it 
temporarily melts the adhesive, but doesn't melt the cel.
his way you can easily peal the sticker of completely in 
tact.
There are a couple of catches though.  
First, if the sticker is very old, it might take a little
pealing work.
Second, if the sticker has been on the cel for a long time,
you might notice a slight indentation in the area where it's 
located.  You can see this, by holding the cel at an angle
and looking at he sticker area.  If ther's an indentation,
that means that the sticker has caused a chemical change in 
the area (namely a mild melt down).  Therefore, I suggest you
decide wheather you'd rather have a visible dent on your cel 
(it will show more dramatically once the sticker is removed,
or if you can tolerate the sticker. 

Good luck! :)

Noriko