To Remove Tamiya Polycarb Spray paint from polycarbonate shell Use a Small Amount of Methylated Spirits
I gave this method a try and it worked, all you have to do is have a rag with a small amount of Methylated Spirits on it and rub the affected area. It will take between 6 and 13 minutes to work. Keep applying small amounts of Meth to the rag and scrubbing, your paitn will come off eventually
REMEMBER: Use Methylated Spirits Outside and Never Breathe it In