The easiest way to use the denatured alcohol, is to soak (I mean REALLY soak) a rag with it, and lay it on the painted area for about a minute. Pick up the rag, pour a little more alcohol on, and rub the paint off. It should just start peeling off, and will eventually just slide off the light. It depends on how long you let the soaked rag sit on the paint and loosen it from the plastic.
Usman
EDIT: Btw, the credit for using denature alcohol goes to Jesse IL...He told CloneGTS about it, who posted it in his write-up...