I had good luck with the alcohol and cornstarch method on my Kenmore fridge. I started with a warm fridge and painted the "slurry" on the top (my model did not have a plastic top on it). After I turned it on, I started brushing the mixture. It was real obvious when it began to dry, there was a line about 7" from the rear where the mixture dried and brushed right off.
Btw, this will only work if you are working right on the metal top of the fridge, did you remove the plastic top?