I have a few cels that also have those nice clear 
seperators. I left them there since (in my 
opinion) they are protecting your investment.

As for the paint removal, I'd be hesitant to try 
anything. I've noticed that cels scratch VERY 
easily while making fan cels of my own. I think 
that I might actually try to leave the paint 
there, or perhaps use a diluted solvent with a 
cotton swab to gently remove the paint. Whatever 
you do try though, just be careful. :)