Steam
I couldn't get the blue film off several panels that were sun dried for several years. I tried alcohol, thinner, mek, glue remover, stripper, sun,hair dryer, iron, heat lamp, you name it.
This morning I finally was able to get it off with a commercial jiffy steamer that I borrowed from momma. It took about 4 hours to do two bottom wing panels. The steam loosened the plastic and off it came with persuasion from a plastic scrapper.
Next time, I'll just reorder the panels from Vans.